diff options
Diffstat (limited to 'tracecmd/trace-vsock.c')
| -rw-r--r-- | tracecmd/trace-vsock.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/tracecmd/trace-vsock.c b/tracecmd/trace-vsock.c new file mode 100644 index 00000000..39294e7a --- /dev/null +++ b/tracecmd/trace-vsock.c @@ -0,0 +1,176 @@ +#include <unistd.h> +#include <errno.h> +#include <arpa/inet.h> +#include <sys/ioctl.h> +#include <linux/vm_sockets.h> + +#include "trace-cmd-private.h" + +int __hidden trace_vsock_open(unsigned int cid, unsigned int port) +{ + struct sockaddr_vm addr = { + .svm_family = AF_VSOCK, + .svm_cid = cid, + .svm_port = port, + }; + int sd; + + sd = socket(AF_VSOCK, SOCK_STREAM, 0); + if (sd < 0) + return -errno; + + if (connect(sd, (struct sockaddr *)&addr, sizeof(addr))) + return -errno; + + return sd; +} + +int __hidden trace_vsock_make(unsigned int port) +{ + struct sockaddr_vm addr = { + .svm_family = AF_VSOCK, + .svm_cid = VMADDR_CID_ANY, + .svm_port = port, + }; + int sd; + + sd = socket(AF_VSOCK, SOCK_STREAM, 0); + if (sd < 0) + return -errno; + + setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &(int){1}, sizeof(int)); + + if (bind(sd, (struct sockaddr *)&addr, sizeof(addr))) + return -errno; + + if (listen(sd, SOMAXCONN)) + return -errno; + + return sd; +} + +int __hidden trace_vsock_make_any(void) +{ + return trace_vsock_make(VMADDR_PORT_ANY); +} + +int __hidden trace_vsock_get_port(int sd, unsigned int *port) +{ + struct sockaddr_vm addr; + socklen_t addr_len = sizeof(addr); + + if (getsockname(sd, (struct sockaddr *)&addr, &addr_len)) + return -errno; + + if (addr.svm_family != AF_VSOCK) + return -EINVAL; + + if (port) + *port = addr.svm_port; + + return 0; +} + +int get_vsocket_params(int fd, unsigned int *lcid, unsigned int *rcid) +{ + struct sockaddr_vm addr; + socklen_t addr_len = sizeof(addr); + + memset(&addr, 0, sizeof(addr)); + if (getsockname(fd, (struct sockaddr *)&addr, &addr_len)) + return -1; + if (addr.svm_family != AF_VSOCK) + return -1; + *lcid = addr.svm_cid; + + memset(&addr, 0, sizeof(addr)); + addr_len = sizeof(addr); + if (getpeername(fd, (struct sockaddr *)&addr, &addr_len)) + return -1; + if (addr.svm_family != AF_VSOCK) + return -1; + *rcid = addr.svm_cid; + + return 0; +} + +int trace_vsock_print_connection(int fd) +{ + struct sockaddr_vm vm_addr; + socklen_t addr_len; + int cid, port; + + addr_len = sizeof(vm_addr); + if (getpeername(fd, (struct sockaddr *)&vm_addr, &addr_len)) + return -1; + if (vm_addr.svm_family != AF_VSOCK) + return -1; + cid = vm_addr.svm_cid; + port = vm_addr.svm_port; + if (tracecmd_get_debug()) + tracecmd_debug("Connected to @%u:%u fd:%d\n", cid, port, fd); + else + tracecmd_plog("Connected to @%u:%u\n", cid, port); + return 0; +} + +static int try_splice_read_vsock(void) +{ + int ret, sd, brass[2]; + + sd = socket(AF_VSOCK, SOCK_STREAM, 0); + if (sd < 0) + return -errno; + + ret = pipe(brass); + if (ret < 0) + goto out_close_sd; + + /* + * On kernels that don't support splice reading from vsockets + * this will fail with EINVAL, or ENOTCONN otherwise. + * Technically, it should never succeed but if it does, claim splice + * reading is supported. + */ + ret = splice(sd, NULL, brass[1], NULL, 10, 0); + if (ret < 0) + ret = errno != EINVAL; + else + ret = 1; + + close(brass[0]); + close(brass[1]); +out_close_sd: + close(sd); + return ret; +} + +bool __hidden trace_vsock_can_splice_read(void) +{ + static bool initialized, res; + + if (initialized) + return res; + + res = try_splice_read_vsock() > 0; + initialized = true; + return res; +} + +#define GET_LOCAL_CID 0x7b9 + +int __hidden trace_vsock_local_cid(void) +{ + int cid; + int fd; + + fd = open("/dev/vsock", O_RDONLY); + if (fd < 0) + return -errno; + + if (ioctl(fd, GET_LOCAL_CID, &cid)) + cid = -errno; + + close(fd); + return cid; +} |