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-rw-r--r--src/fastd.c190
1 files changed, 103 insertions, 87 deletions
diff --git a/src/fastd.c b/src/fastd.c
index 1f606c0..c923efa 100644
--- a/src/fastd.c
+++ b/src/fastd.c
@@ -883,140 +883,156 @@ static void handle_tun(fastd_context_t *ctx) {
}
}
-static void handle_socket(fastd_context_t *ctx, fastd_socket_t *sock) {
- size_t max_len = PACKET_TYPE_LEN + methods_max_packet_size(ctx);
- fastd_buffer_t buffer = fastd_buffer_alloc(ctx, max_len, methods_min_decrypt_head_space(ctx), methods_min_decrypt_tail_space(ctx));
- uint8_t *packet_type;
- fastd_peer_address_t local_addr = {};
-
- fastd_peer_address_t recvaddr;
- struct iovec buffer_vec = { .iov_base = buffer.data, .iov_len = buffer.len };
- char cbuf[1024];
-
- struct msghdr message = {
- .msg_name = &recvaddr,
- .msg_namelen = sizeof(recvaddr),
- .msg_iov = &buffer_vec,
- .msg_iovlen = 1,
- .msg_control = cbuf,
- .msg_controllen = sizeof(cbuf),
- };
-
- ssize_t len = recvmsg(sock->fd, &message, 0);
- if (len <= 0) {
- if (len < 0 && errno != EINTR)
- pr_warn_errno(ctx, "recvmsg");
+static inline void handle_socket_control(fastd_context_t *ctx, struct msghdr *message, const fastd_socket_t *sock, fastd_peer_address_t *local_addr) {
+ memset(local_addr, 0, sizeof(fastd_peer_address_t));
- fastd_buffer_free(buffer);
- return;
- }
+ const char *end = message->msg_control + message->msg_controllen;
struct cmsghdr *cmsg;
- for (cmsg = CMSG_FIRSTHDR(&message); cmsg; cmsg = CMSG_NXTHDR(&message, cmsg)) {
- if ((char*)cmsg + sizeof(*cmsg) > cbuf + sizeof(cbuf))
- break;
+ for (cmsg = CMSG_FIRSTHDR(message); cmsg; cmsg = CMSG_NXTHDR(message, cmsg)) {
+ if ((char*)cmsg + sizeof(*cmsg) > end)
+ return;
if (cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_PKTINFO) {
struct in_pktinfo *pktinfo = (struct in_pktinfo*)CMSG_DATA(cmsg);
- if ((char*)pktinfo + sizeof(*pktinfo) > cbuf + sizeof(cbuf))
- break;
+ if ((char*)pktinfo + sizeof(*pktinfo) > end)
+ return;
- local_addr.in.sin_family = AF_INET;
- local_addr.in.sin_addr = pktinfo->ipi_addr;
- local_addr.in.sin_port = fastd_peer_address_get_port(sock->bound_addr);
+ local_addr->in.sin_family = AF_INET;
+ local_addr->in.sin_addr = pktinfo->ipi_addr;
+ local_addr->in.sin_port = fastd_peer_address_get_port(sock->bound_addr);
- break;
+ return;
}
if (cmsg->cmsg_level == IPPROTO_IPV6 && cmsg->cmsg_type == IPV6_PKTINFO) {
struct in6_pktinfo *pktinfo = (struct in6_pktinfo*)CMSG_DATA(cmsg);
- if ((char*)pktinfo + sizeof(*pktinfo) > cbuf + sizeof(cbuf))
- break;
+ if ((char*)pktinfo + sizeof(*pktinfo) > end)
+ return;
- local_addr.in6.sin6_family = AF_INET6;
- local_addr.in6.sin6_addr = pktinfo->ipi6_addr;
- local_addr.in6.sin6_port = fastd_peer_address_get_port(sock->bound_addr);
+ local_addr->in6.sin6_family = AF_INET6;
+ local_addr->in6.sin6_addr = pktinfo->ipi6_addr;
+ local_addr->in6.sin6_port = fastd_peer_address_get_port(sock->bound_addr);
- if (IN6_IS_ADDR_LINKLOCAL(&local_addr.in6.sin6_addr))
- local_addr.in6.sin6_scope_id = pktinfo->ipi6_ifindex;
+ if (IN6_IS_ADDR_LINKLOCAL(&local_addr->in6.sin6_addr))
+ local_addr->in6.sin6_scope_id = pktinfo->ipi6_ifindex;
- break;
+ return;
}
}
+}
- if (!local_addr.sa.sa_family) {
- pr_error(ctx, "received packet without packet info");
+static inline void handle_socket_receive_known(fastd_context_t *ctx, fastd_socket_t *sock, const fastd_peer_address_t *local_addr, const fastd_peer_address_t *remote_addr, fastd_peer_t *peer, fastd_buffer_t buffer) {
+ if (!fastd_peer_may_connect(ctx, peer)) {
fastd_buffer_free(buffer);
return;
}
- packet_type = buffer.data;
- buffer.len = len;
+ const uint8_t *packet_type = buffer.data;
+ fastd_buffer_push_head(ctx, &buffer, 1);
- fastd_peer_address_simplify(&recvaddr);
+ switch (*packet_type) {
+ case PACKET_DATA:
+ if (!fastd_peer_is_established(peer) || !fastd_peer_address_equal(&peer->local_address, local_addr)) {
+ fastd_buffer_free(buffer);
+ ctx->conf->protocol->handshake_init(ctx, sock, local_addr, remote_addr, NULL);
+ }
+
+ ctx->conf->protocol->handle_recv(ctx, peer, buffer);
+ break;
+
+ case PACKET_HANDSHAKE:
+ fastd_handshake_handle(ctx, sock, local_addr, remote_addr, peer, buffer);
+ }
+}
+static inline bool is_unknown_peer_valid(fastd_context_t *ctx, const fastd_peer_address_t *remote_addr) {
+ return ctx->conf->n_floating || ctx->conf->n_dynamic || ctx->conf->on_verify ||
+ (remote_addr->sa.sa_family == AF_INET && ctx->conf->n_dynamic_v4) ||
+ (remote_addr->sa.sa_family == AF_INET6 && ctx->conf->n_dynamic_v6);
+}
+
+static inline void handle_socket_receive_unknown(fastd_context_t *ctx, fastd_socket_t *sock, const fastd_peer_address_t *local_addr, const fastd_peer_address_t *remote_addr, fastd_buffer_t buffer) {
+ const uint8_t *packet_type = buffer.data;
fastd_buffer_push_head(ctx, &buffer, 1);
+ switch (*packet_type) {
+ case PACKET_DATA:
+ fastd_buffer_free(buffer);
+ ctx->conf->protocol->handshake_init(ctx, sock, local_addr, remote_addr, NULL);
+ break;
+
+ case PACKET_HANDSHAKE:
+ fastd_handshake_handle(ctx, sock, local_addr, remote_addr, NULL, buffer);
+ }
+}
+
+static inline void handle_socket_receive(fastd_context_t *ctx, fastd_socket_t *sock, const fastd_peer_address_t *local_addr, const fastd_peer_address_t *remote_addr, fastd_buffer_t buffer) {
fastd_peer_t *peer = NULL;
if (sock->peer) {
- if (fastd_peer_address_equal(&sock->peer->address, &recvaddr)) {
+ if (fastd_peer_address_equal(&sock->peer->address, remote_addr)) {
peer = sock->peer;
}
}
else {
for (peer = ctx->peers; peer; peer = peer->next) {
- if (fastd_peer_address_equal(&peer->address, &recvaddr))
+ if (fastd_peer_address_equal(&peer->address, remote_addr))
break;
}
}
if (peer) {
- if (!fastd_peer_may_connect(ctx, peer)) {
- fastd_buffer_free(buffer);
- return;
- }
+ handle_socket_receive_known(ctx, sock, local_addr, remote_addr, peer, buffer);
+ }
+ else if(is_unknown_peer_valid(ctx, remote_addr)) {
+ handle_socket_receive_unknown(ctx, sock, local_addr, remote_addr, buffer);
+ }
+ else {
+ pr_debug(ctx, "received packet from unknown peer %I", remote_addr);
+ fastd_buffer_free(buffer);
+ }
+}
- switch (*packet_type) {
- case PACKET_DATA:
- if (fastd_peer_is_established(peer) && fastd_peer_address_equal(&peer->local_address, &local_addr)) {
- ctx->conf->protocol->handle_recv(ctx, peer, buffer);
- }
- else {
- fastd_buffer_free(buffer);
- ctx->conf->protocol->handshake_init(ctx, sock, &local_addr, &recvaddr, NULL);
- }
- break;
+static void handle_socket(fastd_context_t *ctx, fastd_socket_t *sock) {
+ size_t max_len = PACKET_TYPE_LEN + methods_max_packet_size(ctx);
+ fastd_buffer_t buffer = fastd_buffer_alloc(ctx, max_len, methods_min_decrypt_head_space(ctx), methods_min_decrypt_tail_space(ctx));
+ fastd_peer_address_t local_addr;
+ fastd_peer_address_t recvaddr;
+ struct iovec buffer_vec = { .iov_base = buffer.data, .iov_len = buffer.len };
+ char cbuf[1024];
- case PACKET_HANDSHAKE:
- fastd_handshake_handle(ctx, sock, &local_addr, &recvaddr, peer, buffer);
- break;
+ struct msghdr message = {
+ .msg_name = &recvaddr,
+ .msg_namelen = sizeof(recvaddr),
+ .msg_iov = &buffer_vec,
+ .msg_iovlen = 1,
+ .msg_control = cbuf,
+ .msg_controllen = sizeof(cbuf),
+ };
- default:
- fastd_buffer_free(buffer);
- }
+ ssize_t len = recvmsg(sock->fd, &message, 0);
+ if (len <= 0) {
+ if (len < 0 && errno != EINTR)
+ pr_warn_errno(ctx, "recvmsg");
+
+ fastd_buffer_free(buffer);
+ return;
}
- else if(ctx->conf->n_floating || ctx->conf->n_dynamic || ctx->conf->on_verify ||
- (recvaddr.sa.sa_family == AF_INET && ctx->conf->n_dynamic_v4) ||
- (recvaddr.sa.sa_family == AF_INET6 && ctx->conf->n_dynamic_v6)) {
- switch (*packet_type) {
- case PACKET_DATA:
- fastd_buffer_free(buffer);
- ctx->conf->protocol->handshake_init(ctx, sock, &local_addr, &recvaddr, NULL);
- break;
- case PACKET_HANDSHAKE:
- fastd_handshake_handle(ctx, sock, &local_addr, &recvaddr, NULL, buffer);
- break;
+ buffer.len = len;
- default:
- fastd_buffer_free(buffer);
- }
- }
- else {
- pr_debug(ctx, "received packet from unknown peer %I", &recvaddr);
+ handle_socket_control(ctx, &message, sock, &local_addr);
+
+ if (!local_addr.sa.sa_family) {
+ pr_error(ctx, "received packet without packet info");
fastd_buffer_free(buffer);
+ return;
}
+
+ fastd_peer_address_simplify(&recvaddr);
+
+ handle_socket_receive(ctx, sock, &local_addr, &recvaddr, buffer);
}
static void handle_resolv_returns(fastd_context_t *ctx) {
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-09 23:32:42 +0100