Commit f9bc3cbc authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

tools: ynl-gen: support limit names 

Support the use of symbolic names like s8-min or u32-max in checks
to make writing specs less painful.

Link: https://lore.kernel.org/r/20231018163917.2514503-4-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 668c1ac8

Documentation/netlink/genetlink-c.yaml

+7 −2
Original line number Diff line number Diff line
@@ -13,6 +13,11 @@ $defs: 
    type: [ string, integer ]

    pattern: ^[0-9A-Za-z_]+( - 1)?$

    minimum: 0

  len-or-limit:

    # literal int or limit based on fixed-width type e.g. u8-min, u16-max, etc.

    type: [ string, integer ]

    pattern: ^[su](8|16|32|64)-(min|max)$

    minimum: 0



# Schema for specs

title: Protocol
@@ -183,10 +188,10 @@ properties: 
                    type: string

                  min:

                    description: Min value for an integer attribute.

                    type: integer

                    $ref: '#/$defs/len-or-limit'

                  max:

                    description: Max value for an integer attribute.

                    type: integer

                    $ref: '#/$defs/len-or-limit'

                  min-len:

                    description: Min length for a binary attribute.

                    $ref: '#/$defs/len-or-define'

Documentation/netlink/genetlink-legacy.yaml

+7 −2
Original line number Diff line number Diff line
@@ -13,6 +13,11 @@ $defs: 
    type: [ string, integer ]

    pattern: ^[0-9A-Za-z_]+( - 1)?$

    minimum: 0

  len-or-limit:

    # literal int or limit based on fixed-width type e.g. u8-min, u16-max, etc.

    type: [ string, integer ]

    pattern: ^[su](8|16|32|64)-(min|max)$

    minimum: 0



# Schema for specs

title: Protocol
@@ -226,10 +231,10 @@ properties: 
                    type: string

                  min:

                    description: Min value for an integer attribute.

                    type: integer

                    $ref: '#/$defs/len-or-limit'

                  max:

                    description: Max value for an integer attribute.

                    type: integer

                    $ref: '#/$defs/len-or-limit'

                  min-len:

                    description: Min length for a binary attribute.

                    $ref: '#/$defs/len-or-define'

Documentation/netlink/genetlink.yaml

+7 −2
Original line number Diff line number Diff line
@@ -13,6 +13,11 @@ $defs: 
    type: [ string, integer ]

    pattern: ^[0-9A-Za-z_]+( - 1)?$

    minimum: 0

  len-or-limit:

    # literal int or limit based on fixed-width type e.g. u8-min, u16-max, etc.

    type: [ string, integer ]

    pattern: ^[su](8|16|32|64)-(min|max)$

    minimum: 0



# Schema for specs

title: Protocol
@@ -156,10 +161,10 @@ properties: 
                    type: string

                  min:

                    description: Min value for an integer attribute.

                    type: integer

                    $ref: '#/$defs/len-or-limit'

                  max:

                    description: Max value for an integer attribute.

                    type: integer

                    $ref: '#/$defs/len-or-limit'

                  min-len:

                    description: Min length for a binary attribute.

                    $ref: '#/$defs/len-or-define'

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

+34 −11
Original line number Diff line number Diff line
@@ -20,6 +20,21 @@ def c_lower(name): 
    return name.lower().replace('-', '_')





def limit_to_number(name):

    """

    Turn a string limit like u32-max or s64-min into its numerical value

    """

    if name[0] == 'u' and name.endswith('-min'):

        return 0

    width = int(name[1:-4])

    if name[0] == 's':

        width -= 1

    value = (1 << width) - 1

    if name[0] == 's' and name.endswith('-min'):

        value = -value - 1

    return value





class BaseNlLib:

    def get_family_id(self):

        return 'ys->family_id'
@@ -68,6 +83,14 @@ class Type(SpecAttr): 
        self.enum_name = None

        delattr(self, "enum_name")



    def get_limit(self, limit, default=None):

        value = self.checks.get(limit, default)

        if value is None:

            return value

        if not isinstance(value, int):

            value = limit_to_number(value)

        return value



    def resolve(self):

        if 'name-prefix' in self.attr:

            enum_name = f"{self.attr['name-prefix']}{self.name}"
@@ -273,12 +296,12 @@ class TypeScalar(Type): 
                self.checks['max'] = high



        if 'min' in self.checks and 'max' in self.checks:

            if self.checks['min'] > self.checks['max']:

                raise Exception(f'Invalid limit for "{self.name}" min: {self.checks["min"]} max: {self.checks["max"]}')

            if self.get_limit('min') > self.get_limit('max'):

                raise Exception(f'Invalid limit for "{self.name}" min: {self.get_limit("min")} max: {self.get_limit("max")}')

            self.checks['range'] = True



        low = min(self.checks.get('min', 0), self.checks.get('max', 0))

        high = max(self.checks.get('min', 0), self.checks.get('max', 0))

        low = min(self.get_limit('min', 0), self.get_limit('max', 0))

        high = max(self.get_limit('min', 0), self.get_limit('max', 0))

        if low < 0 and self.type[0] == 'u':

            raise Exception(f'Invalid limit for "{self.name}" negative limit for unsigned type')

        if low < -32768 or high > 32767:
@@ -326,11 +349,11 @@ class TypeScalar(Type): 
        elif 'full-range' in self.checks:

            return f"NLA_POLICY_FULL_RANGE({policy}, &{c_lower(self.enum_name)}_range)"

        elif 'range' in self.checks:

            return f"NLA_POLICY_RANGE({policy}, {self.checks['min']}, {self.checks['max']})"

            return f"NLA_POLICY_RANGE({policy}, {self.get_limit('min')}, {self.get_limit('max')})"

        elif 'min' in self.checks:

            return f"NLA_POLICY_MIN({policy}, {self.checks['min']})"

            return f"NLA_POLICY_MIN({policy}, {self.get_limit('min')})"

        elif 'max' in self.checks:

            return f"NLA_POLICY_MAX({policy}, {self.checks['max']})"

            return f"NLA_POLICY_MAX({policy}, {self.get_limit('max')})"

        return super()._attr_policy(policy)



    def _attr_typol(self):
@@ -382,7 +405,7 @@ class TypeString(Type): 
    def _attr_policy(self, policy):

        mem = '{ .type = ' + policy

        if 'max-len' in self.checks:

            mem += ', .len = ' + str(self.checks['max-len'])

            mem += ', .len = ' + str(self.get_limit('max-len'))

        mem += ', }'

        return mem
@@ -431,7 +454,7 @@ class TypeBinary(Type): 
    def _attr_policy(self, policy):

        mem = '{ '

        if len(self.checks) == 1 and 'min-len' in self.checks:

            mem += '.len = ' + str(self.checks['min-len'])

            mem += '.len = ' + str(self.get_limit('min-len'))

        elif len(self.checks) == 0:

            mem += '.type = NLA_BINARY'

        else:
@@ -1982,9 +2005,9 @@ def print_kernel_policy_ranges(family, cw): 
            cw.block_start(line=f'struct netlink_range_validation{sign} {c_lower(attr.enum_name)}_range =')

            members = []

            if 'min' in attr.checks:

                members.append(('min', attr.checks['min']))

                members.append(('min', attr.get_limit('min')))

            if 'max' in attr.checks:

                members.append(('max', attr.checks['max']))

                members.append(('max', attr.get_limit('max')))

            cw.write_struct_init(members)

            cw.block_end(line=';')

            cw.nl()