Message ID | 20241022161009.982584-13-mic@digikod.net (mailing list archive) |
---|---|
State | New |
Delegated to: | Paul Moore |
Headers | show |
Series | Landlock audit support | expand |
Le mardi 22 octobre 2024, 18:10:07 CEST Mickaël Salaün a écrit : > Add audit support to socket_bind and socket_connect hooks. > > Audit record sample: > > DENY: domain=4533720601 blockers=net_connect_tcp daddr=127.0.0.1 > dest=80 SYSCALL: arch=c000003e syscall=42 success=no exit=-13 ... > > Cc: Günther Noack <gnoack@google.com> > Cc: Konstantin Meskhidze <konstantin.meskhidze@huawei.com> > Cc: Mikhail Ivanov <ivanov.mikhail1@huawei-partners.com> > Signed-off-by: Mickaël Salaün <mic@digikod.net> > Link: https://lore.kernel.org/r/20241022161009.982584-13-mic@digikod.net > --- > security/landlock/audit.c | 11 +++++++++ > security/landlock/audit.h | 1 + > security/landlock/net.c | 52 ++++++++++++++++++++++++++++++++++++--- > 3 files changed, 60 insertions(+), 4 deletions(-) > > diff --git a/security/landlock/audit.c b/security/landlock/audit.c > index 898c95ebe847..c31a4a8719ee 100644 > --- a/security/landlock/audit.c > +++ b/security/landlock/audit.c > @@ -41,6 +41,12 @@ static const char *const fs_access_strings[] = { > }; > static_assert(ARRAY_SIZE(fs_access_strings) == LANDLOCK_NUM_ACCESS_FS); > > +static const char *const net_access_strings[] = { > + [BIT_INDEX(LANDLOCK_ACCESS_NET_BIND_TCP)] = "net_bind_tcp", > + [BIT_INDEX(LANDLOCK_ACCESS_NET_CONNECT_TCP)] = "net_connect_tcp", > +}; > +static_assert(ARRAY_SIZE(net_access_strings) == LANDLOCK_NUM_ACCESS_NET); > + > static __attribute_const__ const char * > get_blocker(const enum landlock_request_type type, > const unsigned long access_bit) > @@ -58,6 +64,11 @@ get_blocker(const enum landlock_request_type type, > if (WARN_ON_ONCE(access_bit >= ARRAY_SIZE(fs_access_strings))) > return "unknown"; > return fs_access_strings[access_bit]; > + > + case LANDLOCK_REQUEST_NET_ACCESS: > + if (WARN_ON_ONCE(access_bit >= ARRAY_SIZE(net_access_strings))) > + return "unknown"; > + return net_access_strings[access_bit]; > } > > WARN_ON_ONCE(1); > diff --git a/security/landlock/audit.h b/security/landlock/audit.h > index 320394fd6b84..1075b0c8401f 100644 > --- a/security/landlock/audit.h > +++ b/security/landlock/audit.h > @@ -18,6 +18,7 @@ enum landlock_request_type { > LANDLOCK_REQUEST_PTRACE = 1, > LANDLOCK_REQUEST_FS_CHANGE_LAYOUT, > LANDLOCK_REQUEST_FS_ACCESS, > + LANDLOCK_REQUEST_NET_ACCESS, > }; > > /* > diff --git a/security/landlock/net.c b/security/landlock/net.c > index 27872d0f7e11..c21afd6e0b4d 100644 > --- a/security/landlock/net.c > +++ b/security/landlock/net.c > @@ -7,10 +7,12 @@ > */ > > #include <linux/in.h> > +#include <linux/lsm_audit.h> > #include <linux/net.h> > #include <linux/socket.h> > #include <net/ipv6.h> > > +#include "audit.h" > #include "common.h" > #include "cred.h" > #include "limits.h" > @@ -56,6 +58,10 @@ static int current_check_access_socket(struct socket > *const sock, }; > const struct landlock_ruleset *const dom = > landlock_match_ruleset(landlock_get_current_domain(), any_net); > + struct lsm_network_audit audit_net = {}; > + struct landlock_request request = { > + .type = LANDLOCK_REQUEST_NET_ACCESS, > + }; > > if (!dom) > return 0; > @@ -72,18 +78,49 @@ static int current_check_access_socket(struct socket > *const sock, > > switch (address->sa_family) { > case AF_UNSPEC: > - case AF_INET: > + case AF_INET: { > + const struct sockaddr_in *addr4; > + > if (addrlen < sizeof(struct sockaddr_in)) > return -EINVAL; > - port = ((struct sockaddr_in *)address)->sin_port; > + > + addr4 = (struct sockaddr_in *)address; > + port = addr4->sin_port; > + > + if (access_request == LANDLOCK_ACCESS_NET_CONNECT_TCP) { > + audit_net.dport = port; > + audit_net.v4info.daddr = addr4->sin_addr.s_addr; > + } else if (access_request == LANDLOCK_ACCESS_NET_BIND_TCP) { > + audit_net.sport = port; > + audit_net.v4info.saddr = addr4->sin_addr.s_addr; > + } else { > + WARN_ON_ONCE(1); > + } > break; > + } > > #if IS_ENABLED(CONFIG_IPV6) > - case AF_INET6: > + case AF_INET6: { > + const struct sockaddr_in6 *addr6; > + > if (addrlen < SIN6_LEN_RFC2133) > return -EINVAL; > - port = ((struct sockaddr_in6 *)address)->sin6_port; > + > + addr6 = (struct sockaddr_in6 *)address; > + port = addr6->sin6_port; > + audit_net.v6info.saddr = addr6->sin6_addr; You set this for all access_request, but not for IPv4, is this done on purpose? > + > + if (access_request == LANDLOCK_ACCESS_NET_CONNECT_TCP) { > + audit_net.dport = port; > + audit_net.v6info.daddr = addr6->sin6_addr; > + } else if (access_request == LANDLOCK_ACCESS_NET_BIND_TCP) { > + audit_net.sport = port; > + audit_net.v6info.saddr = addr6->sin6_addr; > + } else { > + WARN_ON_ONCE(1); > + } > break; > + } > #endif /* IS_ENABLED(CONFIG_IPV6) */ > > default: > @@ -152,6 +189,13 @@ static int current_check_access_socket(struct socket > *const sock, ARRAY_SIZE(layer_masks))) > return 0; > > + audit_net.family = address->sa_family; > + request.audit.type = LSM_AUDIT_DATA_NET; > + request.audit.u.net = &audit_net; > + request.access = access_request; > + request.layer_masks = &layer_masks; > + request.layer_masks_size = ARRAY_SIZE(layer_masks); > + landlock_log_denial(dom, &request); > return -EACCES; > }
On Fri, Oct 25, 2024 at 05:25:45PM +0200, Francis Laniel wrote: > Le mardi 22 octobre 2024, 18:10:07 CEST Mickaël Salaün a écrit : > > Add audit support to socket_bind and socket_connect hooks. > > > > Audit record sample: > > > > DENY: domain=4533720601 blockers=net_connect_tcp daddr=127.0.0.1 > > dest=80 SYSCALL: arch=c000003e syscall=42 success=no exit=-13 ... > > > > Cc: Günther Noack <gnoack@google.com> > > Cc: Konstantin Meskhidze <konstantin.meskhidze@huawei.com> > > Cc: Mikhail Ivanov <ivanov.mikhail1@huawei-partners.com> > > Signed-off-by: Mickaël Salaün <mic@digikod.net> > > Link: https://lore.kernel.org/r/20241022161009.982584-13-mic@digikod.net > > --- > > security/landlock/audit.c | 11 +++++++++ > > security/landlock/audit.h | 1 + > > security/landlock/net.c | 52 ++++++++++++++++++++++++++++++++++++--- > > 3 files changed, 60 insertions(+), 4 deletions(-) > > > > diff --git a/security/landlock/audit.c b/security/landlock/audit.c > > index 898c95ebe847..c31a4a8719ee 100644 > > --- a/security/landlock/audit.c > > +++ b/security/landlock/audit.c > > @@ -41,6 +41,12 @@ static const char *const fs_access_strings[] = { > > }; > > static_assert(ARRAY_SIZE(fs_access_strings) == LANDLOCK_NUM_ACCESS_FS); > > > > +static const char *const net_access_strings[] = { > > + [BIT_INDEX(LANDLOCK_ACCESS_NET_BIND_TCP)] = "net_bind_tcp", > > + [BIT_INDEX(LANDLOCK_ACCESS_NET_CONNECT_TCP)] = "net_connect_tcp", > > +}; > > +static_assert(ARRAY_SIZE(net_access_strings) == LANDLOCK_NUM_ACCESS_NET); > > + > > static __attribute_const__ const char * > > get_blocker(const enum landlock_request_type type, > > const unsigned long access_bit) > > @@ -58,6 +64,11 @@ get_blocker(const enum landlock_request_type type, > > if (WARN_ON_ONCE(access_bit >= ARRAY_SIZE(fs_access_strings))) > > return "unknown"; > > return fs_access_strings[access_bit]; > > + > > + case LANDLOCK_REQUEST_NET_ACCESS: > > + if (WARN_ON_ONCE(access_bit >= ARRAY_SIZE(net_access_strings))) > > + return "unknown"; > > + return net_access_strings[access_bit]; > > } > > > > WARN_ON_ONCE(1); > > diff --git a/security/landlock/audit.h b/security/landlock/audit.h > > index 320394fd6b84..1075b0c8401f 100644 > > --- a/security/landlock/audit.h > > +++ b/security/landlock/audit.h > > @@ -18,6 +18,7 @@ enum landlock_request_type { > > LANDLOCK_REQUEST_PTRACE = 1, > > LANDLOCK_REQUEST_FS_CHANGE_LAYOUT, > > LANDLOCK_REQUEST_FS_ACCESS, > > + LANDLOCK_REQUEST_NET_ACCESS, > > }; > > > > /* > > diff --git a/security/landlock/net.c b/security/landlock/net.c > > index 27872d0f7e11..c21afd6e0b4d 100644 > > --- a/security/landlock/net.c > > +++ b/security/landlock/net.c > > @@ -7,10 +7,12 @@ > > */ > > > > #include <linux/in.h> > > +#include <linux/lsm_audit.h> > > #include <linux/net.h> > > #include <linux/socket.h> > > #include <net/ipv6.h> > > > > +#include "audit.h" > > #include "common.h" > > #include "cred.h" > > #include "limits.h" > > @@ -56,6 +58,10 @@ static int current_check_access_socket(struct socket > > *const sock, }; > > const struct landlock_ruleset *const dom = > > landlock_match_ruleset(landlock_get_current_domain(), any_net); > > + struct lsm_network_audit audit_net = {}; > > + struct landlock_request request = { > > + .type = LANDLOCK_REQUEST_NET_ACCESS, > > + }; > > > > if (!dom) > > return 0; > > @@ -72,18 +78,49 @@ static int current_check_access_socket(struct socket > > *const sock, > > > > switch (address->sa_family) { > > case AF_UNSPEC: > > - case AF_INET: > > + case AF_INET: { > > + const struct sockaddr_in *addr4; > > + > > if (addrlen < sizeof(struct sockaddr_in)) > > return -EINVAL; > > - port = ((struct sockaddr_in *)address)->sin_port; > > + > > + addr4 = (struct sockaddr_in *)address; > > + port = addr4->sin_port; > > + > > + if (access_request == LANDLOCK_ACCESS_NET_CONNECT_TCP) { > > + audit_net.dport = port; > > + audit_net.v4info.daddr = addr4->sin_addr.s_addr; > > + } else if (access_request == LANDLOCK_ACCESS_NET_BIND_TCP) { > > + audit_net.sport = port; > > + audit_net.v4info.saddr = addr4->sin_addr.s_addr; > > + } else { > > + WARN_ON_ONCE(1); > > + } > > break; > > + } > > > > #if IS_ENABLED(CONFIG_IPV6) > > - case AF_INET6: > > + case AF_INET6: { > > + const struct sockaddr_in6 *addr6; > > + > > if (addrlen < SIN6_LEN_RFC2133) > > return -EINVAL; > > - port = ((struct sockaddr_in6 *)address)->sin6_port; > > + > > + addr6 = (struct sockaddr_in6 *)address; > > + port = addr6->sin6_port; > > + audit_net.v6info.saddr = addr6->sin6_addr; > > You set this for all access_request, but not for IPv4, is this done on > purpose? Indeed, this is a bug, I'll remove this line. Thanks! > > > + > > + if (access_request == LANDLOCK_ACCESS_NET_CONNECT_TCP) { > > + audit_net.dport = port; > > + audit_net.v6info.daddr = addr6->sin6_addr; > > + } else if (access_request == LANDLOCK_ACCESS_NET_BIND_TCP) { > > + audit_net.sport = port; > > + audit_net.v6info.saddr = addr6->sin6_addr; > > + } else { > > + WARN_ON_ONCE(1); > > + } > > break; > > + } > > #endif /* IS_ENABLED(CONFIG_IPV6) */ > > > > default:
diff --git a/security/landlock/audit.c b/security/landlock/audit.c index 898c95ebe847..c31a4a8719ee 100644 --- a/security/landlock/audit.c +++ b/security/landlock/audit.c @@ -41,6 +41,12 @@ static const char *const fs_access_strings[] = { }; static_assert(ARRAY_SIZE(fs_access_strings) == LANDLOCK_NUM_ACCESS_FS); +static const char *const net_access_strings[] = { + [BIT_INDEX(LANDLOCK_ACCESS_NET_BIND_TCP)] = "net_bind_tcp", + [BIT_INDEX(LANDLOCK_ACCESS_NET_CONNECT_TCP)] = "net_connect_tcp", +}; +static_assert(ARRAY_SIZE(net_access_strings) == LANDLOCK_NUM_ACCESS_NET); + static __attribute_const__ const char * get_blocker(const enum landlock_request_type type, const unsigned long access_bit) @@ -58,6 +64,11 @@ get_blocker(const enum landlock_request_type type, if (WARN_ON_ONCE(access_bit >= ARRAY_SIZE(fs_access_strings))) return "unknown"; return fs_access_strings[access_bit]; + + case LANDLOCK_REQUEST_NET_ACCESS: + if (WARN_ON_ONCE(access_bit >= ARRAY_SIZE(net_access_strings))) + return "unknown"; + return net_access_strings[access_bit]; } WARN_ON_ONCE(1); diff --git a/security/landlock/audit.h b/security/landlock/audit.h index 320394fd6b84..1075b0c8401f 100644 --- a/security/landlock/audit.h +++ b/security/landlock/audit.h @@ -18,6 +18,7 @@ enum landlock_request_type { LANDLOCK_REQUEST_PTRACE = 1, LANDLOCK_REQUEST_FS_CHANGE_LAYOUT, LANDLOCK_REQUEST_FS_ACCESS, + LANDLOCK_REQUEST_NET_ACCESS, }; /* diff --git a/security/landlock/net.c b/security/landlock/net.c index 27872d0f7e11..c21afd6e0b4d 100644 --- a/security/landlock/net.c +++ b/security/landlock/net.c @@ -7,10 +7,12 @@ */ #include <linux/in.h> +#include <linux/lsm_audit.h> #include <linux/net.h> #include <linux/socket.h> #include <net/ipv6.h> +#include "audit.h" #include "common.h" #include "cred.h" #include "limits.h" @@ -56,6 +58,10 @@ static int current_check_access_socket(struct socket *const sock, }; const struct landlock_ruleset *const dom = landlock_match_ruleset(landlock_get_current_domain(), any_net); + struct lsm_network_audit audit_net = {}; + struct landlock_request request = { + .type = LANDLOCK_REQUEST_NET_ACCESS, + }; if (!dom) return 0; @@ -72,18 +78,49 @@ static int current_check_access_socket(struct socket *const sock, switch (address->sa_family) { case AF_UNSPEC: - case AF_INET: + case AF_INET: { + const struct sockaddr_in *addr4; + if (addrlen < sizeof(struct sockaddr_in)) return -EINVAL; - port = ((struct sockaddr_in *)address)->sin_port; + + addr4 = (struct sockaddr_in *)address; + port = addr4->sin_port; + + if (access_request == LANDLOCK_ACCESS_NET_CONNECT_TCP) { + audit_net.dport = port; + audit_net.v4info.daddr = addr4->sin_addr.s_addr; + } else if (access_request == LANDLOCK_ACCESS_NET_BIND_TCP) { + audit_net.sport = port; + audit_net.v4info.saddr = addr4->sin_addr.s_addr; + } else { + WARN_ON_ONCE(1); + } break; + } #if IS_ENABLED(CONFIG_IPV6) - case AF_INET6: + case AF_INET6: { + const struct sockaddr_in6 *addr6; + if (addrlen < SIN6_LEN_RFC2133) return -EINVAL; - port = ((struct sockaddr_in6 *)address)->sin6_port; + + addr6 = (struct sockaddr_in6 *)address; + port = addr6->sin6_port; + audit_net.v6info.saddr = addr6->sin6_addr; + + if (access_request == LANDLOCK_ACCESS_NET_CONNECT_TCP) { + audit_net.dport = port; + audit_net.v6info.daddr = addr6->sin6_addr; + } else if (access_request == LANDLOCK_ACCESS_NET_BIND_TCP) { + audit_net.sport = port; + audit_net.v6info.saddr = addr6->sin6_addr; + } else { + WARN_ON_ONCE(1); + } break; + } #endif /* IS_ENABLED(CONFIG_IPV6) */ default: @@ -152,6 +189,13 @@ static int current_check_access_socket(struct socket *const sock, ARRAY_SIZE(layer_masks))) return 0; + audit_net.family = address->sa_family; + request.audit.type = LSM_AUDIT_DATA_NET; + request.audit.u.net = &audit_net; + request.access = access_request; + request.layer_masks = &layer_masks; + request.layer_masks_size = ARRAY_SIZE(layer_masks); + landlock_log_denial(dom, &request); return -EACCES; }
Add audit support to socket_bind and socket_connect hooks. Audit record sample: DENY: domain=4533720601 blockers=net_connect_tcp daddr=127.0.0.1 dest=80 SYSCALL: arch=c000003e syscall=42 success=no exit=-13 ... Cc: Günther Noack <gnoack@google.com> Cc: Konstantin Meskhidze <konstantin.meskhidze@huawei.com> Cc: Mikhail Ivanov <ivanov.mikhail1@huawei-partners.com> Signed-off-by: Mickaël Salaün <mic@digikod.net> Link: https://lore.kernel.org/r/20241022161009.982584-13-mic@digikod.net --- security/landlock/audit.c | 11 +++++++++ security/landlock/audit.h | 1 + security/landlock/net.c | 52 ++++++++++++++++++++++++++++++++++++--- 3 files changed, 60 insertions(+), 4 deletions(-)