1 /*
2  * (C) 2005-2012 by Pablo Neira Ayuso <pablo@netfilter.org>
3  * (C) 2012 by Vyatta Inc. <http://www.vyatta.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  */
10 
11 #include "internal/internal.h"
12 
exp_cmp(int attr,const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags,int (* cmp)(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags))13 static int exp_cmp(int attr,
14 		   const struct nf_expect *exp1,
15 		   const struct nf_expect *exp2,
16 		   unsigned int flags,
17 		   int (*cmp)(const struct nf_expect *exp1,
18 			      const struct nf_expect *exp2,
19 			      unsigned int flags))
20 {
21 	int a = test_bit(attr, exp1->set);
22 	int b = test_bit(attr, exp2->set);
23 
24 	if (a && b) {
25 		return cmp(exp1, exp2, flags);
26 	} else if (!a && !b) {
27 		return 1;
28 	} else if (flags & NFCT_CMP_MASK &&
29 		   test_bit(attr, exp1->set)) {
30 		return 0;
31 	} else if (flags & NFCT_CMP_STRICT) {
32 		return 0;
33 	}
34 	return 1;
35 }
36 
37 static int
cmp_exp_master(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)38 cmp_exp_master(const struct nf_expect *exp1, const struct nf_expect *exp2,
39 	       unsigned int flags)
40 {
41 	return __cmp_orig((struct nf_conntrack *)&exp1->master,
42 			  (struct nf_conntrack *)&exp2->master, flags);
43 }
44 
45 static int
cmp_exp_expected(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)46 cmp_exp_expected(const struct nf_expect *exp1, const struct nf_expect *exp2,
47 		 unsigned int flags)
48 {
49 	return __cmp_orig((struct nf_conntrack *)&exp1->expected,
50 			  (struct nf_conntrack *)&exp2->expected, flags);
51 }
52 
53 static int
cmp_exp_mask(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)54 cmp_exp_mask(const struct nf_expect *exp1, const struct nf_expect *exp2,
55 	     unsigned int flags)
56 {
57 	return __cmp_orig((struct nf_conntrack *)&exp1->mask,
58 			  (struct nf_conntrack *)&exp2->mask, flags);
59 
60 }
61 
62 static int
cmp_exp_zone(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)63 cmp_exp_zone(const struct nf_expect *exp1, const struct nf_expect *exp2,
64 	     unsigned int flags)
65 {
66 	return exp1->zone == exp2->zone;
67 }
68 
69 static int
cmp_exp_flags(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)70 cmp_exp_flags(const struct nf_expect *exp1, const struct nf_expect *exp2,
71 	      unsigned int flags)
72 {
73 	return (exp1->flags == exp2->flags);
74 }
75 
76 static int
cmp_exp_hname(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)77 cmp_exp_hname(const struct nf_expect *exp1, const struct nf_expect *exp2,
78 	      unsigned int flags)
79 {
80 	return strcmp(exp1->helper_name, exp2->helper_name) == 0;
81 }
82 
83 static int
cmp_exp_class(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)84 cmp_exp_class(const struct nf_expect *exp1, const struct nf_expect *exp2,
85 	      unsigned int flags)
86 {
87 	return (exp1->class == exp2->class);
88 }
89 
90 static int
cmp_exp_natt(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)91 cmp_exp_natt(const struct nf_expect *exp1, const struct nf_expect *exp2,
92 	     unsigned int flags)
93 {
94 	return __cmp_orig((struct nf_conntrack *)&exp1->nat,
95 			  (struct nf_conntrack *)&exp2->nat, flags);
96 
97 }
98 
99 static int
cmp_exp_natdir(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)100 cmp_exp_natdir(const struct nf_expect *exp1, const struct nf_expect *exp2,
101 	       unsigned int flags)
102 {
103 	return exp1->nat_dir == exp2->nat_dir;
104 }
105 
106 static int
cmp_exp_expfn(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)107 cmp_exp_expfn(const struct nf_expect *exp1, const struct nf_expect *exp2,
108 	      unsigned int flags)
109 {
110 	return strcmp(exp1->expectfn, exp2->expectfn) == 0;
111 }
112 
113 
__cmp_expect(const struct nf_expect * exp1,const struct nf_expect * exp2,unsigned int flags)114 int __cmp_expect(const struct nf_expect *exp1,
115 		 const struct nf_expect *exp2,
116 		 unsigned int flags)
117 {
118 	if (!exp_cmp(ATTR_EXP_MASTER, exp1, exp2, flags, cmp_exp_master))
119 		return 0;
120 	if (!exp_cmp(ATTR_EXP_EXPECTED, exp1, exp2, flags, cmp_exp_expected))
121 		return 0;
122 	if (!exp_cmp(ATTR_EXP_MASK, exp1, exp2, flags, cmp_exp_mask))
123 		return 0;
124 	/* ATTR_EXP_TIMEOUT is intentionally not compared at this time; the expectations should
125 	 * be considered equal if only the timeout is different */
126 	if (!exp_cmp(ATTR_EXP_ZONE, exp1, exp2, flags, cmp_exp_zone))
127 		return 0;
128 	if (!exp_cmp(ATTR_EXP_FLAGS, exp1, exp2, flags, cmp_exp_flags))
129 		return 0;
130 	if (!exp_cmp(ATTR_EXP_HELPER_NAME, exp1, exp2, flags, cmp_exp_hname))
131 		return 0;
132 	if (!exp_cmp(ATTR_EXP_CLASS, exp1, exp2, flags, cmp_exp_class))
133 		return 0;
134 	if (!exp_cmp(ATTR_EXP_NAT_TUPLE, exp1, exp2, flags, cmp_exp_natt))
135 		return 0;
136 	if (!exp_cmp(ATTR_EXP_NAT_DIR, exp1, exp2, flags, cmp_exp_natdir))
137 		return 0;
138 	if (!exp_cmp(ATTR_EXP_FN, exp1, exp2, flags, cmp_exp_expfn))
139 		return 0;
140 	return 1;
141 }
142