Use some macros to increase readabiltiy of BPF rules
Bu işleme şunda yer alıyor:
ebeveyn
77adf09d34
işleme
ca0f82790c
122
exile.h
122
exile.h
@ -68,13 +68,6 @@
|
||||
#error Seccomp support has not been tested for exile.h for this platform yet
|
||||
#endif
|
||||
|
||||
#define SYSCALL(nr, jt) \
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, (nr), 0, 1), jt
|
||||
|
||||
|
||||
#define EXILE_BPF_NOP \
|
||||
BPF_STMT(BPF_JMP+BPF_JA,0)
|
||||
|
||||
#define EXILE_UNSHARE_NETWORK 1<<1
|
||||
#define EXILE_UNSHARE_USER 1<<2
|
||||
#define EXILE_UNSHARE_MOUNT 1<<3
|
||||
@ -263,6 +256,34 @@ struct exile_path_policy
|
||||
#define EXILE_SYSCALL_DENY_KILL_PROCESS 2
|
||||
#define EXILE_SYSCALL_DENY_RET_ERROR 3
|
||||
|
||||
#define EXILE_BPF_NOP \
|
||||
BPF_STMT(BPF_JMP+BPF_JA,0)
|
||||
|
||||
#define EXILE_BPF_LOAD_SECCOMP_ARG(nr) \
|
||||
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, (offsetof(struct seccomp_data, args[nr])))
|
||||
|
||||
#define EXILE_BPF_CMP_EQ(val,t,f) \
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, val, t, f)
|
||||
|
||||
#define EXILE_BPF_CMP_SET(val,t,f) \
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, val, t, f)
|
||||
|
||||
/* Immediatly go to the syscall action, do not process any other arg filters */
|
||||
#define EXILE_BPF_MATCH(argval) \
|
||||
EXILE_BPF_CMP_EQ(argval, EXILE_SYSCALL_EXIT_BPF_RETURN, 0)
|
||||
|
||||
#define EXILE_BPF_MATCH_SET(argval) \
|
||||
EXILE_BPF_CMP_SET(argval, EXILE_SYSCALL_EXIT_BPF_RETURN, 0)
|
||||
|
||||
/* Immediatly go beyond the syscall action, do not process any other arg filters. What to do with this syscall
|
||||
is thus up to the default policy */
|
||||
#define EXILE_BPF_NO_MATCH(argval) \
|
||||
EXILE_BPF_CMP_EQ(argval, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0)
|
||||
|
||||
#define EXILE_BPF_NO_MATCH_SET(argval) \
|
||||
EXILE_BPF_CMP_SET(argval, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0)
|
||||
|
||||
|
||||
/* Pledge definitions */
|
||||
#define EXILE_SYSCALL_PLEDGE_CHOWN ((uint64_t)1<<1)
|
||||
#define EXILE_SYSCALL_PLEDGE_CLONE ((uint64_t)1<<2)
|
||||
@ -645,64 +666,71 @@ int exile_append_syscall_default_policy(struct exile_policy *exile_policy, unsig
|
||||
|
||||
static int get_pledge_argfilter(long syscall, uint64_t pledge_promises, struct sock_filter *filter)
|
||||
{
|
||||
|
||||
/* How to read this:
|
||||
* Keep in mind our default action is do deny, unless it's a syscall from an pledge promise. Then it will be
|
||||
* accepted if the argument values are good (if we care about them at all).
|
||||
* EXILE_BPF_MATCH() means the argument value is good, and the syscall can be accepted
|
||||
* EXILE_BPF_NO_MATCH() means the syscall won't be allowed because the value is illegal
|
||||
*/
|
||||
struct sock_filter mmap_no_exec[] = {
|
||||
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, (offsetof(struct seccomp_data, args[2]))),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, PROT_EXEC, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0)};
|
||||
EXILE_BPF_LOAD_SECCOMP_ARG(2),
|
||||
EXILE_BPF_NO_MATCH(PROT_EXEC)
|
||||
};
|
||||
|
||||
struct sock_filter ioctl_default[] = {
|
||||
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, (offsetof(struct seccomp_data, args[1]))),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, FIONREAD, EXILE_SYSCALL_EXIT_BPF_RETURN, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, FIONBIO, EXILE_SYSCALL_EXIT_BPF_RETURN, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, FIOCLEX, EXILE_SYSCALL_EXIT_BPF_RETURN, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, FIONCLEX, EXILE_SYSCALL_EXIT_BPF_RETURN, EXILE_SYSCALL_EXIT_BPF_NO_MATCH)
|
||||
};
|
||||
EXILE_BPF_LOAD_SECCOMP_ARG(1),
|
||||
EXILE_BPF_MATCH(FIONREAD),
|
||||
EXILE_BPF_MATCH(FIONBIO),
|
||||
EXILE_BPF_MATCH(FIOCLEX),
|
||||
EXILE_BPF_CMP_EQ(FIONCLEX, EXILE_SYSCALL_EXIT_BPF_RETURN, EXILE_SYSCALL_EXIT_BPF_NO_MATCH)
|
||||
};
|
||||
|
||||
/* open() and friends with read-only flags */
|
||||
struct sock_filter open_rdonly[] = {
|
||||
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, (offsetof(struct seccomp_data, args[1]))),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, O_CREAT, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, O_TMPFILE, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, O_WRONLY, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, O_RDWR, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, O_APPEND, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
EXILE_BPF_LOAD_SECCOMP_ARG(1),
|
||||
EXILE_BPF_NO_MATCH_SET(O_CREAT),
|
||||
EXILE_BPF_NO_MATCH_SET(O_TMPFILE),
|
||||
EXILE_BPF_NO_MATCH_SET(O_WRONLY),
|
||||
EXILE_BPF_NO_MATCH_SET(O_RDWR),
|
||||
EXILE_BPF_NO_MATCH_SET(O_APPEND),
|
||||
};
|
||||
|
||||
struct sock_filter socket_filter[4] = {
|
||||
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, (offsetof(struct seccomp_data, args[0]))),
|
||||
EXILE_BPF_LOAD_SECCOMP_ARG(0),
|
||||
EXILE_BPF_NOP,
|
||||
EXILE_BPF_NOP,
|
||||
EXILE_BPF_NOP
|
||||
};
|
||||
|
||||
struct sock_filter setsockopt_filter[] = {
|
||||
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, (offsetof(struct seccomp_data, args[2]))),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, SO_DEBUG, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, SO_SNDBUFFORCE, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0)
|
||||
EXILE_BPF_LOAD_SECCOMP_ARG(2),
|
||||
EXILE_BPF_NO_MATCH(SO_DEBUG),
|
||||
EXILE_BPF_NO_MATCH(SO_SNDBUFFORCE)
|
||||
};
|
||||
|
||||
|
||||
struct sock_filter clone_filter[] = {
|
||||
/* It's the first argument for x86_64 */
|
||||
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, (offsetof(struct seccomp_data, args[0]))),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, CLONE_VM, 0, EXILE_SYSCALL_EXIT_BPF_NO_MATCH),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, CLONE_THREAD, 0, EXILE_SYSCALL_EXIT_BPF_NO_MATCH),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, CLONE_NEWCGROUP, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, CLONE_NEWIPC, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, CLONE_NEWNET, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, CLONE_NEWNS, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, CLONE_NEWPID, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, CLONE_NEWUSER, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, CLONE_NEWUTS, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0)
|
||||
EXILE_BPF_LOAD_SECCOMP_ARG(0),
|
||||
EXILE_BPF_NO_MATCH_SET(CLONE_VM),
|
||||
EXILE_BPF_NO_MATCH_SET(CLONE_THREAD),
|
||||
EXILE_BPF_NO_MATCH_SET(CLONE_NEWCGROUP),
|
||||
EXILE_BPF_NO_MATCH_SET(CLONE_NEWIPC),
|
||||
EXILE_BPF_NO_MATCH_SET(CLONE_NEWNET),
|
||||
EXILE_BPF_NO_MATCH_SET(CLONE_NEWNS),
|
||||
EXILE_BPF_NO_MATCH_SET(CLONE_NEWPID),
|
||||
EXILE_BPF_NO_MATCH_SET(CLONE_NEWUSER),
|
||||
EXILE_BPF_NO_MATCH_SET(CLONE_NEWUTS),
|
||||
};
|
||||
|
||||
struct sock_filter prctl_default[] ={
|
||||
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, (offsetof(struct seccomp_data, args[0]))),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, PR_SET_NO_NEW_PRIVS, EXILE_SYSCALL_EXIT_BPF_RETURN, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, PR_GET_NO_NEW_PRIVS, EXILE_SYSCALL_EXIT_BPF_RETURN, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, PR_GET_NAME, EXILE_SYSCALL_EXIT_BPF_RETURN, 0),
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, PR_SET_NAME, EXILE_SYSCALL_EXIT_BPF_RETURN, 0),
|
||||
EXILE_BPF_NOP,
|
||||
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, PR_CAPBSET_READ, EXILE_SYSCALL_EXIT_BPF_RETURN, EXILE_SYSCALL_EXIT_BPF_NO_MATCH),
|
||||
EXILE_BPF_LOAD_SECCOMP_ARG(0),
|
||||
EXILE_BPF_MATCH(PR_SET_NO_NEW_PRIVS),
|
||||
EXILE_BPF_MATCH(PR_GET_NO_NEW_PRIVS),
|
||||
EXILE_BPF_MATCH(PR_GET_NAME),
|
||||
EXILE_BPF_MATCH(PR_SET_NAME),
|
||||
EXILE_BPF_CMP_EQ(PR_CAPBSET_READ, EXILE_SYSCALL_EXIT_BPF_RETURN, EXILE_SYSCALL_EXIT_BPF_NO_MATCH),
|
||||
};
|
||||
|
||||
int result = 0;
|
||||
@ -769,14 +797,14 @@ static int get_pledge_argfilter(long syscall, uint64_t pledge_promises, struct s
|
||||
case EXILE_SYS(socket):
|
||||
if(pledge_promises & EXILE_SYSCALL_PLEDGE_UNIX)
|
||||
{
|
||||
socket_filter[current_filter_index] = (struct sock_filter) BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, AF_UNIX, EXILE_SYSCALL_EXIT_BPF_RETURN, 0);
|
||||
socket_filter[current_filter_index] = (struct sock_filter) EXILE_BPF_MATCH(AF_UNIX);
|
||||
++current_filter_index;
|
||||
}
|
||||
if(pledge_promises & EXILE_SYSCALL_PLEDGE_INET)
|
||||
{
|
||||
socket_filter[current_filter_index] = (struct sock_filter) BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, AF_INET, EXILE_SYSCALL_EXIT_BPF_RETURN, 0);
|
||||
socket_filter[current_filter_index] = (struct sock_filter) EXILE_BPF_MATCH(AF_INET);
|
||||
++current_filter_index;
|
||||
socket_filter[current_filter_index] = (struct sock_filter) BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, AF_INET6, EXILE_SYSCALL_EXIT_BPF_RETURN, 0);
|
||||
socket_filter[current_filter_index] = (struct sock_filter) EXILE_BPF_MATCH(AF_INET6);
|
||||
++current_filter_index;
|
||||
}
|
||||
socket_filter[current_filter_index-1].jf = EXILE_SYSCALL_EXIT_BPF_NO_MATCH;
|
||||
@ -804,7 +832,7 @@ static int get_pledge_argfilter(long syscall, uint64_t pledge_promises, struct s
|
||||
}
|
||||
if(pledge_promises & EXILE_SYSCALL_PLEDGE_SECCOMP_INSTALL)
|
||||
{
|
||||
prctl_default[3] = (struct sock_filter) BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, PR_SET_SECCOMP, EXILE_SYSCALL_EXIT_BPF_RETURN, 0);
|
||||
prctl_default[3] = (struct sock_filter) EXILE_BPF_MATCH(PR_SET_SECCOMP);
|
||||
}
|
||||
result = sizeof(prctl_default)/sizeof(prctl_default[0]);
|
||||
memcpy(filter, prctl_default, sizeof(prctl_default));
|
||||
@ -1278,7 +1306,7 @@ static void append_syscall_to_bpf(struct exile_syscall_policy *syscallpolicy, st
|
||||
/* TODO: Return error */
|
||||
return;
|
||||
}
|
||||
struct sock_filter syscall_check = BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, (unsigned int) syscall, 0, next_syscall_pc);
|
||||
struct sock_filter syscall_check = EXILE_BPF_CMP_EQ((unsigned int) syscall, 0, next_syscall_pc);
|
||||
filter[(*start_index)++] = syscall_check;
|
||||
--next_syscall_pc;
|
||||
|
||||
|
Yükleniyor…
Yeni konuda referans
Bir kullanıcı engelle