github.com/imran-kn/cilium-fork@v1.6.9/pkg/policy/policy.go (about)

     1  // Copyright 2016-2019 Authors of Cilium
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package policy
    16  
    17  import (
    18  	"fmt"
    19  	"io"
    20  	"strconv"
    21  	"strings"
    22  
    23  	"github.com/cilium/cilium/api/v1/models"
    24  	"github.com/cilium/cilium/pkg/labels"
    25  	"github.com/cilium/cilium/pkg/policy/api"
    26  
    27  	"github.com/op/go-logging"
    28  )
    29  
    30  type Tracing int
    31  
    32  const (
    33  	TRACE_DISABLED Tracing = iota
    34  	TRACE_ENABLED
    35  	TRACE_VERBOSE
    36  )
    37  
    38  // TraceEnabled returns true if the SearchContext requests tracing.
    39  func (s *SearchContext) TraceEnabled() bool {
    40  	return s.Trace != TRACE_DISABLED
    41  }
    42  
    43  // PolicyTrace logs the given message into the SearchContext logger only if
    44  // TRACE_ENABLED or TRACE_VERBOSE is enabled in the receiver's SearchContext.
    45  func (s *SearchContext) PolicyTrace(format string, a ...interface{}) {
    46  	if s.TraceEnabled() {
    47  		log.Debugf(format, a...)
    48  		if s.Logging != nil {
    49  			format = "%-" + s.CallDepth() + "s" + format
    50  			a = append([]interface{}{""}, a...)
    51  			s.Logging.Logger.Printf(format, a...)
    52  		}
    53  	}
    54  }
    55  
    56  // PolicyTraceVerbose logs the given message into the SearchContext logger only
    57  // if TRACE_VERBOSE is enabled in the receiver's SearchContext.
    58  func (s *SearchContext) PolicyTraceVerbose(format string, a ...interface{}) {
    59  	switch s.Trace {
    60  	case TRACE_VERBOSE:
    61  		log.Debugf(format, a...)
    62  		if s.Logging != nil {
    63  			s.Logging.Logger.Printf(format, a...)
    64  		}
    65  	}
    66  }
    67  
    68  // SearchContext defines the context while evaluating policy
    69  type SearchContext struct {
    70  	Trace   Tracing
    71  	Depth   int
    72  	Logging *logging.LogBackend
    73  	From    labels.LabelArray
    74  	To      labels.LabelArray
    75  	DPorts  []*models.Port
    76  	// rulesSelect specifies whether or not to check whether a rule which is
    77  	// being analyzed using this SearchContext matches either From or To.
    78  	// This is used to avoid using EndpointSelector.Matches() if possible,
    79  	// since it is costly in terms of performance.
    80  	rulesSelect bool
    81  }
    82  
    83  func (s *SearchContext) String() string {
    84  	from := []string{}
    85  	to := []string{}
    86  	dports := []string{}
    87  	for _, fromLabel := range s.From {
    88  		from = append(from, fromLabel.String())
    89  	}
    90  	for _, toLabel := range s.To {
    91  		to = append(to, toLabel.String())
    92  	}
    93  	for _, dport := range s.DPorts {
    94  		dports = append(dports, fmt.Sprintf("%d/%s", dport.Port, dport.Protocol))
    95  	}
    96  	ret := fmt.Sprintf("From: [%s]", strings.Join(from, ", "))
    97  	ret += fmt.Sprintf(" => To: [%s]", strings.Join(to, ", "))
    98  	if len(dports) != 0 {
    99  		ret += fmt.Sprintf(" Ports: [%s]", strings.Join(dports, ", "))
   100  	}
   101  	return ret
   102  }
   103  
   104  func (s *SearchContext) CallDepth() string {
   105  	return strconv.Itoa(s.Depth * 2)
   106  }
   107  
   108  // WithLogger returns a shallow copy of the received SearchContext with the
   109  // logging set to write to 'log'.
   110  func (s *SearchContext) WithLogger(log io.Writer) *SearchContext {
   111  	result := *s
   112  	result.Logging = logging.NewLogBackend(log, "", 0)
   113  	if result.Trace == TRACE_DISABLED {
   114  		result.Trace = TRACE_ENABLED
   115  	}
   116  	return &result
   117  }
   118  
   119  // Translator is an interface for altering policy rules
   120  type Translator interface {
   121  	Translate(*api.Rule, *TranslationResult) error
   122  }