#ifndef __SOCKET_HELPERS__
#define __SOCKET_HELPERS__
#include <sys/un.h>
#include <linux/vm_sockets.h>
#define SOCK_TYPE_MASK 0xf
#define IO_TIMEOUT_SEC 30
#define MAX_STRERR_LEN 256
#ifndef VMADDR_CID_LOCAL
#define VMADDR_CID_LOCAL 1
#endif
#if __STDC_VERSION__ < 202311L && !defined(auto)
# define auto __auto_type
#endif
#define __get_and_null(p, nullvalue) \
({ \
auto __ptr = &(p); \
auto __val = *__ptr; \
*__ptr = nullvalue; \
__val; \
})
#define take_fd(fd) __get_and_null(fd, -EBADF)
#define _FAIL(errnum, fmt...) \
({ \
error_at_line(0, (errnum), __func__, __LINE__, fmt); \
CHECK_FAIL(true); \
})
#define FAIL(fmt...) _FAIL(0, fmt)
#define FAIL_ERRNO(fmt...) _FAIL(errno, fmt)
#define FAIL_LIBBPF(err, msg) \
({ \
char __buf[MAX_STRERR_LEN]; \
libbpf_strerror((err), __buf, sizeof(__buf)); \
FAIL("%s: %s", (msg), __buf); \
})
#define xaccept_nonblock(fd, addr, len) \
({ \
int __ret = \
accept_timeout((fd), (addr), (len), IO_TIMEOUT_SEC); \
if (__ret == -1) \
FAIL_ERRNO("accept"); \
__ret; \
})
#define xbind(fd, addr, len) \
({ \
int __ret = bind((fd), (addr), (len)); \
if (__ret == -1) \
FAIL_ERRNO("bind"); \
__ret; \
})
#define xclose(fd) \
({ \
int __ret = close((fd)); \
if (__ret == -1) \
FAIL_ERRNO("close"); \
__ret; \
})
#define xconnect(fd, addr, len) \
({ \
int __ret = connect((fd), (addr), (len)); \
if (__ret == -1) \
FAIL_ERRNO("connect"); \
__ret; \
})
#define xgetsockname(fd, addr, len) \
({ \
int __ret = getsockname((fd), (addr), (len)); \
if (__ret == -1) \
FAIL_ERRNO("getsockname"); \
__ret; \
})
#define xgetsockopt(fd, level, name, val, len) \
({ \
int __ret = getsockopt((fd), (level), (name), (val), (len)); \
if (__ret == -1) \
FAIL_ERRNO("getsockopt(" #name ")"); \
__ret; \
})
#define xlisten(fd, backlog) \
({ \
int __ret = listen((fd), (backlog)); \
if (__ret == -1) \
FAIL_ERRNO("listen"); \
__ret; \
})
#define xsetsockopt(fd, level, name, val, len) \
({ \
int __ret = setsockopt((fd), (level), (name), (val), (len)); \
if (__ret == -1) \
FAIL_ERRNO("setsockopt(" #name ")"); \
__ret; \
})
#define xsend(fd, buf, len, flags) \
({ \
ssize_t __ret = send((fd), (buf), (len), (flags)); \
if (__ret == -1) \
FAIL_ERRNO("send"); \
__ret; \
})
#define xrecv_nonblock(fd, buf, len, flags) \
({ \
ssize_t __ret = recv_timeout((fd), (buf), (len), (flags), \
IO_TIMEOUT_SEC); \
if (__ret == -1) \
FAIL_ERRNO("recv"); \
__ret; \
})
#define xsocket(family, sotype, flags) \
({ \
int __ret = socket(family, sotype, flags); \
if (__ret == -1) \
FAIL_ERRNO("socket"); \
__ret; \
})
static inline void close_fd(int *fd)
{
if (*fd >= 0)
xclose(*fd);
}
#define __close_fd __attribute__((cleanup(close_fd)))
static inline struct sockaddr *sockaddr(struct sockaddr_storage *ss)
{
return (struct sockaddr *)ss;
}
static inline void init_addr_loopback4(struct sockaddr_storage *ss,
socklen_t *len)
{
struct sockaddr_in *addr4 = memset(ss, 0, sizeof(*ss));
addr4->sin_family = AF_INET;
addr4->sin_port = 0;
addr4->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
*len = sizeof(*addr4);
}
static inline void init_addr_loopback6(struct sockaddr_storage *ss,
socklen_t *len)
{
struct sockaddr_in6 *addr6 = memset(ss, 0, sizeof(*ss));
addr6->sin6_family = AF_INET6;
addr6->sin6_port = 0;
addr6->sin6_addr = in6addr_loopback;
*len = sizeof(*addr6);
}
static inline void init_addr_loopback_unix(struct sockaddr_storage *ss,
socklen_t *len)
{
struct sockaddr_un *addr = memset(ss, 0, sizeof(*ss));
addr->sun_family = AF_UNIX;
*len = sizeof(sa_family_t);
}
static inline void init_addr_loopback_vsock(struct sockaddr_storage *ss,
socklen_t *len)
{
struct sockaddr_vm *addr = memset(ss, 0, sizeof(*ss));
addr->svm_family = AF_VSOCK;
addr->svm_port = VMADDR_PORT_ANY;
addr->svm_cid = VMADDR_CID_LOCAL;
*len = sizeof(*addr);
}
static inline void init_addr_loopback(int family, struct sockaddr_storage *ss,
socklen_t *len)
{
switch (family) {
case AF_INET:
init_addr_loopback4(ss, len);
return;
case AF_INET6:
init_addr_loopback6(ss, len);
return;
case AF_UNIX:
init_addr_loopback_unix(ss, len);
return;
case AF_VSOCK:
init_addr_loopback_vsock(ss, len);
return;
default:
FAIL("unsupported address family %d", family);
}
}
static inline int enable_reuseport(int s, int progfd)
{
int err, one = 1;
err = xsetsockopt(s, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one));
if (err)
return -1;
err = xsetsockopt(s, SOL_SOCKET, SO_ATTACH_REUSEPORT_EBPF, &progfd,
sizeof(progfd));
if (err)
return -1;
return 0;
}
static inline int socket_loopback_reuseport(int family, int sotype, int progfd)
{
struct sockaddr_storage addr;
socklen_t len = 0;
int err, s;
init_addr_loopback(family, &addr, &len);
s = xsocket(family, sotype, 0);
if (s == -1)
return -1;
if (progfd >= 0)
enable_reuseport(s, progfd);
err = xbind(s, sockaddr(&addr), len);
if (err)
goto close;
if (sotype & SOCK_DGRAM)
return s;
err = xlisten(s, SOMAXCONN);
if (err)
goto close;
return s;
close:
xclose(s);
return -1;
}
static inline int socket_loopback(int family, int sotype)
{
return socket_loopback_reuseport(family, sotype, -1);
}
static inline int poll_connect(int fd, unsigned int timeout_sec)
{
struct timeval timeout = { .tv_sec = timeout_sec };
fd_set wfds;
int r, eval;
socklen_t esize = sizeof(eval);
FD_ZERO(&wfds);
FD_SET(fd, &wfds);
r = select(fd + 1, NULL, &wfds, NULL, &timeout);
if (r == 0)
errno = ETIME;
if (r != 1)
return -1;
if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &eval, &esize) < 0)
return -1;
if (eval != 0) {
errno = eval;
return -1;
}
return 0;
}
static inline int poll_read(int fd, unsigned int timeout_sec)
{
struct timeval timeout = { .tv_sec = timeout_sec };
fd_set rfds;
int r;
FD_ZERO(&rfds);
FD_SET(fd, &rfds);
r = select(fd + 1, &rfds, NULL, NULL, &timeout);
if (r == 0)
errno = ETIME;
return r == 1 ? 0 : -1;
}
static inline int accept_timeout(int fd, struct sockaddr *addr, socklen_t *len,
unsigned int timeout_sec)
{
if (poll_read(fd, timeout_sec))
return -1;
return accept(fd, addr, len);
}
static inline int recv_timeout(int fd, void *buf, size_t len, int flags,
unsigned int timeout_sec)
{
if (poll_read(fd, timeout_sec))
return -1;
return recv(fd, buf, len, flags);
}
static inline int create_pair(int family, int sotype, int *p0, int *p1)
{
__close_fd int s, c = -1, p = -1;
struct sockaddr_storage addr;
socklen_t len;
int err;
s = socket_loopback(family, sotype);
if (s < 0)
return s;
c = xsocket(family, sotype, 0);
if (c < 0)
return c;
init_addr_loopback(family, &addr, &len);
err = xbind(c, sockaddr(&addr), len);
if (err)
return err;
len = sizeof(addr);
err = xgetsockname(s, sockaddr(&addr), &len);
if (err)
return err;
err = connect(c, sockaddr(&addr), len);
if (err) {
if (errno != EINPROGRESS) {
FAIL_ERRNO("connect");
return err;
}
err = poll_connect(c, IO_TIMEOUT_SEC);
if (err) {
FAIL_ERRNO("poll_connect");
return err;
}
}
switch (sotype & SOCK_TYPE_MASK) {
case SOCK_DGRAM:
err = xgetsockname(c, sockaddr(&addr), &len);
if (err)
return err;
err = xconnect(s, sockaddr(&addr), len);
if (err)
return err;
*p0 = take_fd(s);
break;
case SOCK_STREAM:
case SOCK_SEQPACKET:
p = xaccept_nonblock(s, NULL, NULL);
if (p < 0)
return p;
*p0 = take_fd(p);
break;
default:
FAIL("Unsupported socket type %#x", sotype);
return -EOPNOTSUPP;
}
*p1 = take_fd(c);
return 0;
}
static inline int create_socket_pairs(int family, int sotype, int *c0, int *c1,
int *p0, int *p1)
{
int err;
err = create_pair(family, sotype, c0, p0);
if (err)
return err;
err = create_pair(family, sotype, c1, p1);
if (err) {
close(*c0);
close(*p0);
}
return err;
}
static inline const char *socket_kind_to_str(int sock_fd)
{
socklen_t opt_len;
int domain, type;
opt_len = sizeof(domain);
if (getsockopt(sock_fd, SOL_SOCKET, SO_DOMAIN, &domain, &opt_len))
FAIL_ERRNO("getsockopt(SO_DOMAIN)");
opt_len = sizeof(type);
if (getsockopt(sock_fd, SOL_SOCKET, SO_TYPE, &type, &opt_len))
FAIL_ERRNO("getsockopt(SO_TYPE)");
switch (domain) {
case AF_INET:
switch (type) {
case SOCK_STREAM:
return "tcp4";
case SOCK_DGRAM:
return "udp4";
}
break;
case AF_INET6:
switch (type) {
case SOCK_STREAM:
return "tcp6";
case SOCK_DGRAM:
return "udp6";
}
break;
case AF_UNIX:
switch (type) {
case SOCK_STREAM:
return "u_str";
case SOCK_DGRAM:
return "u_dgr";
case SOCK_SEQPACKET:
return "u_seq";
}
break;
case AF_VSOCK:
switch (type) {
case SOCK_STREAM:
return "v_str";
case SOCK_DGRAM:
return "v_dgr";
case SOCK_SEQPACKET:
return "v_seq";
}
break;
}
return "???";
}
#endif
