Merge branch 'tools-ynl-generate-code-for-the-handshake-family'

Jakub Kicinski says:

====================
tools: ynl: generate code for the handshake family

Add necessary features and generate user space C code for serializing
/ deserializing messages of the handshake family.

In addition to basics already present in netdev and fou, handshake
has nested attrs and multi-attr u32.
====================

Link: https://lore.kernel.org/r/20230606194302.919343-1-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

tools/net/ynl/generated/Makefile

@@ -9,7 +9,7 @@ endif
 
 TOOL:=../ynl-gen-c.py
 
-GENS:=fou netdev
+GENS:=handshake fou netdev
 SRCS=$(patsubst %,%-user.c,${GENS})
 HDRS=$(patsubst %,%-user.h,${GENS})
 OBJS=$(patsubst %,%-user.o,${GENS})

tools/net/ynl/generated/handshake-user.h

+/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */
+/* Do not edit directly, auto-generated from: */
+/*	Documentation/netlink/specs/handshake.yaml */
+/* YNL-GEN user header */
+
+#ifndef _LINUX_HANDSHAKE_GEN_H
+#define _LINUX_HANDSHAKE_GEN_H
+
+#include <stdlib.h>
+#include <string.h>
+#include <linux/types.h>
+#include <linux/handshake.h>
+
+struct ynl_sock;
+
+extern const struct ynl_family ynl_handshake_family;
+
+/* Enums */
+const char *handshake_op_str(int op);
+const char *handshake_handler_class_str(enum handshake_handler_class value);
+const char *handshake_msg_type_str(enum handshake_msg_type value);
+const char *handshake_auth_str(enum handshake_auth value);
+
+/* Common nested types */
+struct handshake_x509 {
+	struct {
+		__u32 cert:1;
+		__u32 privkey:1;
+	} _present;
+
+	__u32 cert;
+	__u32 privkey;
+};
+
+/* ============== HANDSHAKE_CMD_ACCEPT ============== */
+/* HANDSHAKE_CMD_ACCEPT - do */
+struct handshake_accept_req {
+	struct {
+		__u32 handler_class:1;
+	} _present;
+
+	enum handshake_handler_class handler_class;
+};
+
+static inline struct handshake_accept_req *handshake_accept_req_alloc(void)
+{
+	return calloc(1, sizeof(struct handshake_accept_req));
+}
+void handshake_accept_req_free(struct handshake_accept_req *req);
+
+static inline void
+handshake_accept_req_set_handler_class(struct handshake_accept_req *req,
+				       enum handshake_handler_class handler_class)
+{
+	req->_present.handler_class = 1;
+	req->handler_class = handler_class;
+}
+
+struct handshake_accept_rsp {
+	struct {
+		__u32 sockfd:1;
+		__u32 message_type:1;
+		__u32 timeout:1;
+		__u32 auth_mode:1;
+		__u32 peername_len;
+	} _present;
+
+	__u32 sockfd;
+	enum handshake_msg_type message_type;
+	__u32 timeout;
+	enum handshake_auth auth_mode;
+	unsigned int n_peer_identity;
+	__u32 *peer_identity;
+	unsigned int n_certificate;
+	struct handshake_x509 *certificate;
+	char *peername;
+};
+
+void handshake_accept_rsp_free(struct handshake_accept_rsp *rsp);
+
+/*
+ * Handler retrieves next queued handshake request
+ */
+struct handshake_accept_rsp *
+handshake_accept(struct ynl_sock *ys, struct handshake_accept_req *req);
+
+/* HANDSHAKE_CMD_ACCEPT - notify */
+struct handshake_accept_ntf {
+	__u16 family;
+	__u8 cmd;
+	struct ynl_ntf_base_type *next;
+	void (*free)(struct handshake_accept_ntf *ntf);
+	struct handshake_accept_rsp obj __attribute__ ((aligned (8)));
+};
+
+void handshake_accept_ntf_free(struct handshake_accept_ntf *rsp);
+
+/* ============== HANDSHAKE_CMD_DONE ============== */
+/* HANDSHAKE_CMD_DONE - do */
+struct handshake_done_req {
+	struct {
+		__u32 status:1;
+		__u32 sockfd:1;
+	} _present;
+
+	__u32 status;
+	__u32 sockfd;
+	unsigned int n_remote_auth;
+	__u32 *remote_auth;
+};
+
+static inline struct handshake_done_req *handshake_done_req_alloc(void)
+{
+	return calloc(1, sizeof(struct handshake_done_req));
+}
+void handshake_done_req_free(struct handshake_done_req *req);
+
+static inline void
+handshake_done_req_set_status(struct handshake_done_req *req, __u32 status)
+{
+	req->_present.status = 1;
+	req->status = status;
+}
+static inline void
+handshake_done_req_set_sockfd(struct handshake_done_req *req, __u32 sockfd)
+{
+	req->_present.sockfd = 1;
+	req->sockfd = sockfd;
+}
+static inline void
+__handshake_done_req_set_remote_auth(struct handshake_done_req *req,
+				     __u32 *remote_auth,
+				     unsigned int n_remote_auth)
+{
+	free(req->remote_auth);
+	req->remote_auth = remote_auth;
+	req->n_remote_auth = n_remote_auth;
+}
+
+/*
+ * Handler reports handshake completion
+ */
+int handshake_done(struct ynl_sock *ys, struct handshake_done_req *req);
+
+/* --------------- Common notification parsing --------------- */
+struct ynl_ntf_base_type *handshake_ntf_parse(struct ynl_sock *ys);
+
+#endif /* _LINUX_HANDSHAKE_GEN_H */

tools/net/ynl/ynl-gen-c.py

@@ -94,7 +94,10 @@ class Type(SpecAttr):
     def arg_member(self, ri):
         member = self._complex_member_type(ri)
         if member:
-            return [member + ' *' + self.c_name]
+            arg = [member + ' *' + self.c_name]
+            if self.presence_type() == 'count':
+                arg += ['unsigned int n_' + self.c_name]
+            return arg
         raise Exception(f"Struct member not implemented for class type {self.type}")
 
     def struct_member(self, ri):
@@ -188,9 +191,12 @@ class Type(SpecAttr):
                 code.append(presence + ' = 1;')
         code += self._setter_lines(ri, member, presence)
 
-        ri.cw.write_func('static inline void',
-                         f"{op_prefix(ri, direction, deref=deref)}_set_{'_'.join(ref)}",
-                         body=code,
+        func_name = f"{op_prefix(ri, direction, deref=deref)}_set_{'_'.join(ref)}"
+        free = bool([x for x in code if 'free(' in x])
+        alloc = bool([x for x in code if 'alloc(' in x])
+        if free and not alloc:
+            func_name = '__' + func_name
+        ri.cw.write_func('static inline void', func_name, body=code,
                          args=[f'{type_name(ri, direction, deref=deref)} *{var}'] + self.arg_member(ri))
 
 
@@ -444,6 +450,13 @@ class TypeMultiAttr(Type):
     def presence_type(self):
         return 'count'
 
+    def _mnl_type(self):
+        t = self.type
+        # mnl does not have a helper for signed types
+        if t[0] == 's':
+            t = 'u' + t[1:]
+        return t
+
     def _complex_member_type(self, ri):
         if 'type' not in self.attr or self.attr['type'] == 'nest':
             return f"struct {self.nested_render_name}"
@@ -457,9 +470,14 @@ class TypeMultiAttr(Type):
         return 'type' not in self.attr or self.attr['type'] == 'nest'
 
     def free(self, ri, var, ref):
-        if 'type' not in self.attr or self.attr['type'] == 'nest':
+        if self.attr['type'] in scalars:
+            ri.cw.p(f"free({var}->{ref}{self.c_name});")
+        elif 'type' not in self.attr or self.attr['type'] == 'nest':
             ri.cw.p(f"for (i = 0; i < {var}->{ref}n_{self.c_name}; i++)")
             ri.cw.p(f'{self.nested_render_name}_free(&{var}->{ref}{self.c_name}[i]);')
+            ri.cw.p(f"free({var}->{ref}{self.c_name});")
+        else:
+            raise Exception(f"Free of MultiAttr sub-type {self.attr['type']} not supported yet")
 
     def _attr_typol(self):
         if 'type' not in self.attr or self.attr['type'] == 'nest':
@@ -470,7 +488,26 @@ class TypeMultiAttr(Type):
             raise Exception(f"Sub-type {self.attr['type']} not supported yet")
 
     def _attr_get(self, ri, var):
-        return f'{var}->n_{self.c_name}++;', None, None
+        return f'n_{self.c_name}++;', None, None
+
+    def attr_put(self, ri, var):
+        if self.attr['type'] in scalars:
+            put_type = self._mnl_type()
+            ri.cw.p(f"for (unsigned int i = 0; i < {var}->n_{self.c_name}; i++)")
+            ri.cw.p(f"mnl_attr_put_{put_type}(nlh, {self.enum_name}, {var}->{self.c_name}[i]);")
+        elif 'type' not in self.attr or self.attr['type'] == 'nest':
+            ri.cw.p(f"for (unsigned int i = 0; i < {var}->n_{self.c_name}; i++)")
+            self._attr_put_line(ri, var, f"{self.nested_render_name}_put(nlh, " +
+                                f"{self.enum_name}, &{var}->{self.c_name}[i])")
+        else:
+            raise Exception(f"Put of MultiAttr sub-type {self.attr['type']} not supported yet")
+
+    def _setter_lines(self, ri, member, presence):
+        # For multi-attr we have a count, not presence, hack up the presence
+        presence = presence[:-(len('_present.') + len(self.c_name))] + "n_" + self.c_name
+        return [f"free({member});",
+                f"{member} = {self.c_name};",
+                f"{presence} = n_{self.c_name};"]
 
 
 class TypeArrayNest(Type):
@@ -1269,6 +1306,11 @@ def _multi_parse(ri, struct, init_lines, local_vars):
         local_vars.append('struct ynl_parse_arg parg;')
         init_lines.append('parg.ys = yarg->ys;')
 
+    all_multi = array_nests | multi_attrs
+
+    for anest in sorted(all_multi):
+        local_vars.append(f"unsigned int n_{struct[anest].c_name} = 0;")
+
     ri.cw.block_start()
     ri.cw.write_func_lvar(local_vars)
 
@@ -1279,6 +1321,11 @@ def _multi_parse(ri, struct, init_lines, local_vars):
     for arg in struct.inherited:
         ri.cw.p(f'dst->{arg} = {arg};')
 
+    for anest in sorted(all_multi):
+        aspec = struct[anest]
+        ri.cw.p(f"if (dst->{aspec.c_name})")
+        ri.cw.p(f'return ynl_error_parse(yarg, "attribute already present ({struct.attr_set.name}.{aspec.name})");')
+
     ri.cw.nl()
     ri.cw.block_start(line=iter_line)
 
@@ -1294,8 +1341,9 @@ def _multi_parse(ri, struct, init_lines, local_vars):
     for anest in sorted(array_nests):
         aspec = struct[anest]
 
-        ri.cw.block_start(line=f"if (dst->n_{aspec.c_name})")
-        ri.cw.p(f"dst->{aspec.c_name} = calloc(dst->n_{aspec.c_name}, sizeof(*dst->{aspec.c_name}));")
+        ri.cw.block_start(line=f"if (n_{aspec.c_name})")
+        ri.cw.p(f"dst->{aspec.c_name} = calloc({aspec.c_name}, sizeof(*dst->{aspec.c_name}));")
+        ri.cw.p(f"dst->n_{aspec.c_name} = n_{aspec.c_name};")
         ri.cw.p('i = 0;')
         ri.cw.p(f"parg.rsp_policy = &{aspec.nested_render_name}_nest;")
         ri.cw.block_start(line=f"mnl_attr_for_each_nested(attr, attr_{aspec.c_name})")
@@ -1309,8 +1357,9 @@ def _multi_parse(ri, struct, init_lines, local_vars):
 
     for anest in sorted(multi_attrs):
         aspec = struct[anest]
-        ri.cw.block_start(line=f"if (dst->n_{aspec.c_name})")
-        ri.cw.p(f"dst->{aspec.c_name} = calloc(dst->n_{aspec.c_name}, sizeof(*dst->{aspec.c_name}));")
+        ri.cw.block_start(line=f"if (n_{aspec.c_name})")
+        ri.cw.p(f"dst->{aspec.c_name} = calloc(n_{aspec.c_name}, sizeof(*dst->{aspec.c_name}));")
+        ri.cw.p(f"dst->n_{aspec.c_name} = n_{aspec.c_name};")
         ri.cw.p('i = 0;')
         if 'nested-attributes' in aspec:
             ri.cw.p(f"parg.rsp_policy = &{aspec.nested_render_name}_nest;")