1 /* $NetBSD: valid_mailhost_addr.c,v 1.1.1.1 2009/06/23 10:08:47 tron Exp $ */
2
3 /*++
4 /* NAME
5 /* valid_mailhost_addr 3
6 /* SUMMARY
7 /* mailhost address syntax validation
8 /* SYNOPSIS
9 /* #include <valid_mailhost_addr.h>
10 /*
11 /* const char *valid_mailhost_addr(name, gripe)
12 /* const char *name;
13 /* int gripe;
14 /*
15 /* int valid_mailhost_literal(addr, gripe)
16 /* const char *addr;
17 /* int gripe;
18 /* DESCRIPTION
19 /* valid_mailhost_addr() requires that the input is a valid
20 /* RFC 2821 string representation of an IPv4 or IPv6 network
21 /* address. A valid IPv4 address is in dotted quad decimal
22 /* form. A valid IPv6 address includes the "IPV6:" prefix as
23 /* required by RFC 2821, and is in valid hexadecimal form or
24 /* in valid IPv4-in-IPv6 form. The result value is the bare
25 /* address in the input argument (i.e. text after "IPV6:"
26 /* prefix, if any) in case of success, a null pointer in case
27 /* of failure.
28 /*
29 /* valid_mailhost_literal() requires an address enclosed in
30 /* []. The result is non-zero in case of success, zero in
31 /* case of failure.
32 /*
33 /* These routines operate silently unless the gripe parameter
34 /* specifies a non-zero value. The macros DO_GRIPE and DONT_GRIPE
35 /* provide suitable constants.
36 /*
37 /* The IPV6_COL macro defines the "IPv6:" prefix.
38 /* DIAGNOSTICS
39 /* Warnings are logged with msg_warn().
40 /* SEE ALSO
41 /* valid_hostname(3)
42 /* RFC 952, RFC 1123, RFC 1035, RFC 2821
43 /* LICENSE
44 /* .ad
45 /* .fi
46 /* The Secure Mailer license must be distributed with this software.
47 /* AUTHOR(S)
48 /* Wietse Venema
49 /* IBM T.J. Watson Research
50 /* P.O. Box 704
51 /* Yorktown Heights, NY 10598, USA
52 /*--*/
53
54
55 /* System library. */
56
57 #include <sys_defs.h>
58 #include <string.h>
59
60 #ifdef STRCASECMP_IN_STRINGS_H
61 #include <strings.h>
62 #endif
63
64 /* Utility library. */
65
66 #include <msg.h>
67 #include <myaddrinfo.h>
68
69 /* Global library. */
70
71 #include <valid_mailhost_addr.h>
72
73 /* Application-specific. */
74
75 #define IPV6_COL_LEN (sizeof(IPV6_COL) - 1)
76 #define HAS_IPV6_COL(str) (strncasecmp((str), IPV6_COL, IPV6_COL_LEN) == 0)
77 #define SKIP_IPV6_COL(str) (HAS_IPV6_COL(str) ? (str) + IPV6_COL_LEN : (str))
78
79 /* valid_mailhost_addr - validate RFC 2821 numerical address form */
80
valid_mailhost_addr(const char * addr,int gripe)81 const char *valid_mailhost_addr(const char *addr, int gripe)
82 {
83 const char *bare_addr;
84
85 bare_addr = SKIP_IPV6_COL(addr);
86 return ((bare_addr != addr ? valid_ipv6_hostaddr : valid_ipv4_hostaddr)
87 (bare_addr, gripe) ? bare_addr : 0);
88 }
89
90 /* valid_mailhost_literal - validate [RFC 2821 numerical address] form */
91
valid_mailhost_literal(const char * addr,int gripe)92 int valid_mailhost_literal(const char *addr, int gripe)
93 {
94 const char *myname = "valid_mailhost_literal";
95 MAI_HOSTADDR_STR hostaddr;
96 const char *last;
97 size_t address_bytes;
98
99 if (*addr != '[') {
100 if (gripe)
101 msg_warn("%s: '[' expected at start: %.100s", myname, addr);
102 return (0);
103 }
104 if ((last = strchr(addr, ']')) == 0) {
105 if (gripe)
106 msg_warn("%s: ']' expected at end: %.100s", myname, addr);
107 return (0);
108 }
109 if (last[1]) {
110 if (gripe)
111 msg_warn("%s: unexpected text after ']': %.100s", myname, addr);
112 return (0);
113 }
114 if ((address_bytes = last - addr - 1) >= sizeof(hostaddr.buf)) {
115 if (gripe)
116 msg_warn("%s: too much text: %.100s", myname, addr);
117 return (0);
118 }
119 strncpy(hostaddr.buf, addr + 1, address_bytes);
120 hostaddr.buf[address_bytes] = 0;
121 return (valid_mailhost_addr(hostaddr.buf, gripe) != 0);
122 }
123
124 #ifdef TEST
125
126 /*
127 * Test program - reads hostnames from stdin, reports invalid hostnames to
128 * stderr.
129 */
130 #include <stdlib.h>
131
132 #include <vstring.h>
133 #include <vstream.h>
134 #include <vstring_vstream.h>
135 #include <msg_vstream.h>
136
main(int unused_argc,char ** argv)137 int main(int unused_argc, char **argv)
138 {
139 VSTRING *buffer = vstring_alloc(1);
140
141 msg_vstream_init(argv[0], VSTREAM_ERR);
142 msg_verbose = 1;
143
144 while (vstring_fgets_nonl(buffer, VSTREAM_IN)) {
145 msg_info("testing: \"%s\"", vstring_str(buffer));
146 if (vstring_str(buffer)[0] == '[')
147 valid_mailhost_literal(vstring_str(buffer), DO_GRIPE);
148 else
149 valid_mailhost_addr(vstring_str(buffer), DO_GRIPE);
150 }
151 exit(0);
152 }
153
154 #endif
155