[core] Add support for vsock transport

BUILD

@@ -1287,6 +1287,7 @@ grpc_cc_library(
         "//src/core:lib/iomgr/tcp_windows.cc",
         "//src/core:lib/iomgr/unix_sockets_posix.cc",
         "//src/core:lib/iomgr/unix_sockets_posix_noop.cc",
+        "//src/core:lib/iomgr/vsock.cc",
         "//src/core:lib/iomgr/wakeup_fd_eventfd.cc",
         "//src/core:lib/iomgr/wakeup_fd_nospecial.cc",
         "//src/core:lib/iomgr/wakeup_fd_pipe.cc",
@@ -1386,6 +1387,7 @@ grpc_cc_library(
         "//src/core:lib/iomgr/tcp_server_utils_posix.h",
         "//src/core:lib/iomgr/tcp_windows.h",
         "//src/core:lib/iomgr/unix_sockets_posix.h",
+        "//src/core:lib/iomgr/vsock.h",
         "//src/core:lib/iomgr/wakeup_fd_pipe.h",
         "//src/core:lib/iomgr/wakeup_fd_posix.h",
         "//src/core:lib/resource_quota/api.h",

src/core/ext/filters/client_channel/http_proxy.cc

@@ -180,6 +180,11 @@ absl::optional<std::string> HttpProxyMapper::MapName(
             std::string(server_uri).c_str());
     return absl::nullopt;
   }
+  if (uri->scheme() == "vsock") {
+    gpr_log(GPR_INFO, "not using proxy for VSock '%s'",
+            std::string(server_uri).c_str());
+    return absl::nullopt;
+  }
   // Prefer using 'no_grpc_proxy'. Fallback on 'no_proxy' if it is not set.
   auto no_proxy_str = GetEnv("no_grpc_proxy");
   if (!no_proxy_str.has_value()) {

src/core/ext/filters/client_channel/resolver/sockaddr/README.md

@@ -1 +1 @@
-Support for resolving ipv4:, ipv6:, unix: schemes
+Support for resolving ipv4:, ipv6:, unix:, vsock: schemes

src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.cc

@@ -172,6 +172,26 @@ class UnixAbstractResolverFactory : public ResolverFactory {
 };
 #endif  // GRPC_HAVE_UNIX_SOCKET
 
+#ifdef GRPC_HAVE_VSOCK
+class VSockResolverFactory : public ResolverFactory {
+ public:
+  bool IsValidUri(const URI& uri) const override {
+    return ParseUri(uri, grpc_parse_vsock, nullptr);
+  }
+
+  OrphanablePtr<Resolver> CreateResolver(ResolverArgs args) const override {
+    return CreateSockaddrResolver(std::move(args), grpc_parse_vsock);
+  }
+
+  std::string GetDefaultAuthority(const URI& /*uri*/) const override {
+    return "localhost";
+  }
+
+  absl::string_view scheme() const override { return "vsock"; }
+};
+
+#endif  // GRPC_HAVE_VSOCK
+
 }  // namespace
 
 void RegisterSockaddrResolver(CoreConfiguration::Builder* builder) {
@@ -185,6 +205,10 @@ void RegisterSockaddrResolver(CoreConfiguration::Builder* builder) {
   builder->resolver_registry()->RegisterResolverFactory(
       std::make_unique<UnixAbstractResolverFactory>());
 #endif
+#ifdef GRPC_HAVE_VSOCK
+  builder->resolver_registry()->RegisterResolverFactory(
+      absl::make_unique<VSockResolverFactory>());
+#endif
 }
 
 }  // namespace grpc_core

src/core/ext/transport/chttp2/server/chttp2_server.cc

@@ -71,6 +71,7 @@
 #include "src/core/lib/iomgr/resolved_address.h"
 #include "src/core/lib/iomgr/tcp_server.h"
 #include "src/core/lib/iomgr/unix_sockets_posix.h"
+#include "src/core/lib/iomgr/vsock.h"
 #include "src/core/lib/resource_quota/memory_quota.h"
 #include "src/core/lib/resource_quota/resource_quota.h"
 #include "src/core/lib/security/credentials/credentials.h"
@@ -98,6 +99,7 @@ using ::grpc_event_engine::experimental::EventEngine;
 
 const char kUnixUriPrefix[] = "unix:";
 const char kUnixAbstractUriPrefix[] = "unix-abstract:";
+const char kVSockUriPrefix[] = "vsock:";
 
 class Chttp2ServerListener : public Server::ListenerInterface {
  public:
@@ -941,6 +943,8 @@ grpc_error_handle Chttp2ServerAddPort(Server* server, const char* addr,
                                    kUnixAbstractUriPrefix)) {
       resolved_or =
           grpc_resolve_unix_abstract_domain_address(parsed_addr_unprefixed);
+    } else if (absl::ConsumePrefix(&parsed_addr_unprefixed, kVSockUriPrefix)) {
+      resolved_or = grpc_resolve_vsock_address(parsed_addr_unprefixed);
     } else {
       resolved_or =
           GetDNSResolver()->LookupHostnameBlocking(parsed_addr, "https");

src/core/lib/address_utils/parse_address.cc

@@ -26,6 +26,9 @@
 #ifdef GRPC_HAVE_UNIX_SOCKET
 #include <sys/un.h>
 #endif
+#ifdef GRPC_HAVE_VSOCK
+#include <linux/vm_sockets.h>
+#endif
 #include <string>
 
 #include "absl/status/status.h"
@@ -144,6 +147,60 @@ grpc_error_handle UnixAbstractSockaddrPopulate(
 }  // namespace grpc_core
 #endif  // GRPC_HAVE_UNIX_SOCKET
 
+#ifdef GRPC_HAVE_VSOCK
+
+bool grpc_parse_vsock(const grpc_core::URI& uri,
+                      grpc_resolved_address* resolved_addr) {
+  if (uri.scheme() != "vsock") {
+    gpr_log(GPR_ERROR, "Expected 'vsock' scheme, got '%s'",
+            uri.scheme().c_str());
+    return false;
+  }
+  grpc_error_handle error =
+      grpc_core::VSockaddrPopulate(uri.path(), resolved_addr);
+  if (!error.ok()) {
+    gpr_log(GPR_ERROR, "%s", grpc_core::StatusToString(error).c_str());
+    return false;
+  }
+  return true;
+}
+
+namespace grpc_core {
+
+grpc_error_handle VSockaddrPopulate(absl::string_view path,
+                                    grpc_resolved_address* resolved_addr) {
+  memset(resolved_addr, 0, sizeof(*resolved_addr));
+  struct sockaddr_vm* vm =
+      reinterpret_cast<struct sockaddr_vm*>(resolved_addr->addr);
+  vm->svm_family = AF_VSOCK;
+  std::string s = std::string(path);
+  if (sscanf(s.c_str(), "%u:%u", &vm->svm_cid, &vm->svm_port) != 2) {
+    return GRPC_ERROR_CREATE(
+        absl::StrCat("Failed to parse vsock cid/port: ", s));
+  }
+  resolved_addr->len = static_cast<socklen_t>(sizeof(*vm));
+  return absl::OkStatus();
+}
+
+}  // namespace grpc_core
+
+#else   // GRPC_HAVE_VSOCK
+
+bool grpc_parse_vsock(const grpc_core::URI& /* uri */,
+                      grpc_resolved_address* /* resolved_addr */) {
+  abort();
+}
+
+namespace grpc_core {
+
+grpc_error_handle VSockaddrPopulate(
+    absl::string_view /* path */, grpc_resolved_address* /* resolved_addr */) {
+  abort();
+}
+
+}  // namespace grpc_core
+#endif  // GRPC_HAVE_VSOCK
+
 bool grpc_parse_ipv4_hostport(absl::string_view hostport,
                               grpc_resolved_address* addr, bool log_errors) {
   bool success = false;
@@ -299,6 +356,9 @@ bool grpc_parse_uri(const grpc_core::URI& uri,
   if (uri.scheme() == "unix-abstract") {
     return grpc_parse_unix_abstract(uri, resolved_addr);
   }
+  if (uri.scheme() == "vsock") {
+    return grpc_parse_vsock(uri, resolved_addr);
+  }
   if (uri.scheme() == "ipv4") {
     return grpc_parse_ipv4(uri, resolved_addr);
   }

src/core/lib/address_utils/parse_address.h

@@ -40,6 +40,11 @@ bool grpc_parse_unix(const grpc_core::URI& uri,
 bool grpc_parse_unix_abstract(const grpc_core::URI& uri,
                               grpc_resolved_address* resolved_addr);
 
+/// Populate \a resolved_addr from \a uri, whose path is expected to contain a
+/// vsock cid:port pair. Returns true upon success.
+bool grpc_parse_vsock(const grpc_core::URI& uri,
+                      grpc_resolved_address* resolved_addr);
+
 /// Populate \a resolved_addr from \a uri, whose path is expected to contain an
 /// IPv4 host:port pair. Returns true upon success.
 bool grpc_parse_ipv4(const grpc_core::URI& uri,
@@ -81,6 +86,9 @@ grpc_error_handle UnixSockaddrPopulate(absl::string_view path,
 grpc_error_handle UnixAbstractSockaddrPopulate(
     absl::string_view path, grpc_resolved_address* resolved_addr);
 
+/// Populate \a resolved_addr to be a vsock at |path|
+grpc_error_handle VSockaddrPopulate(absl::string_view path,
+                                    grpc_resolved_address* resolved_addr);
 }  // namespace grpc_core
 
 #endif  // GRPC_SRC_CORE_LIB_ADDRESS_UTILS_PARSE_ADDRESS_H