1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
|
/*++
/* NAME
/* xtext 3
/* SUMMARY
/* quote/unquote text, xtext style.
/* SYNOPSIS
/* #include <xtext.h>
/*
/* VSTRING *xtext_quote(quoted, unquoted, special)
/* VSTRING *quoted;
/* const char *unquoted;
/* const char *special;
/*
/* VSTRING *xtext_quote_append(unquoted, quoted, special)
/* VSTRING *unquoted;
/* const char *quoted;
/* const char *special;
/*
/* VSTRING *xtext_unquote(unquoted, quoted)
/* VSTRING *unquoted;
/* const char *quoted;
/*
/* VSTRING *xtext_unquote_append(unquoted, quoted)
/* VSTRING *unquoted;
/* const char *quoted;
/* DESCRIPTION
/* xtext_quote() takes a null-terminated string and replaces characters
/* +, <33(10) and >126(10), as well as characters specified with "special"
/* by +XX, XX being the two-digit uppercase hexadecimal equivalent.
/*
/* xtext_quote_append() is like xtext_quote(), but appends the conversion
/* result to the result buffer.
/*
/* xtext_unquote() performs the opposite transformation. This function
/* understands lowercase, uppercase, and mixed case +XX sequences. The
/* result value is the unquoted argument in case of success, a null pointer
/* otherwise.
/*
/* xtext_unquote_append() is like xtext_unquote(), but appends
/* the conversion result to the result buffer.
/* BUGS
/* This module cannot process null characters in data.
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*
/* Wietse Venema
/* Google, Inc.
/* 111 8th Avenue
/* New York, NY 10011, USA
/*--*/
/* System library. */
#include <sys_defs.h>
#include <string.h>
#include <ctype.h>
/* Utility library. */
#include "msg.h"
#include "vstring.h"
#include "xtext.h"
/* Application-specific. */
#define STR(x) vstring_str(x)
#define LEN(x) VSTRING_LEN(x)
/* xtext_quote_append - append unquoted data to quoted data */
VSTRING *xtext_quote_append(VSTRING *quoted, const char *unquoted,
const char *special)
{
const char *cp;
int ch;
for (cp = unquoted; (ch = *(unsigned const char *) cp) != 0; cp++) {
if (ch != '+' && ch > 32 && ch < 127
&& (*special == 0 || strchr(special, ch) == 0)) {
VSTRING_ADDCH(quoted, ch);
} else {
vstring_sprintf_append(quoted, "+%02X", ch);
}
}
VSTRING_TERMINATE(quoted);
return (quoted);
}
/* xtext_quote - unquoted data to quoted */
VSTRING *xtext_quote(VSTRING *quoted, const char *unquoted, const char *special)
{
VSTRING_RESET(quoted);
xtext_quote_append(quoted, unquoted, special);
return (quoted);
}
/* xtext_unquote_append - quoted data to unquoted */
VSTRING *xtext_unquote_append(VSTRING *unquoted, const char *quoted)
{
const unsigned char *cp;
int ch;
for (cp = (const unsigned char *) quoted; (ch = *cp) != 0; cp++) {
if (ch == '+') {
if (ISDIGIT(cp[1]))
ch = (cp[1] - '0') << 4;
else if (cp[1] >= 'a' && cp[1] <= 'f')
ch = (cp[1] - 'a' + 10) << 4;
else if (cp[1] >= 'A' && cp[1] <= 'F')
ch = (cp[1] - 'A' + 10) << 4;
else
return (0);
if (ISDIGIT(cp[2]))
ch |= (cp[2] - '0');
else if (cp[2] >= 'a' && cp[2] <= 'f')
ch |= (cp[2] - 'a' + 10);
else if (cp[2] >= 'A' && cp[2] <= 'F')
ch |= (cp[2] - 'A' + 10);
else
return (0);
cp += 2;
}
VSTRING_ADDCH(unquoted, ch);
}
VSTRING_TERMINATE(unquoted);
return (unquoted);
}
/* xtext_unquote - quoted data to unquoted */
VSTRING *xtext_unquote(VSTRING *unquoted, const char *quoted)
{
VSTRING_RESET(unquoted);
return (xtext_unquote_append(unquoted, quoted) ? unquoted : 0);
}
#ifdef TEST
/*
* Proof-of-concept test program: convert to quoted and back.
*/
#include <vstream.h>
#define BUFLEN 1024
static ssize_t read_buf(VSTREAM *fp, VSTRING *buf)
{
ssize_t len;
len = vstream_fread_buf(fp, buf, BUFLEN);
VSTRING_TERMINATE(buf);
return (len);
}
int main(int unused_argc, char **unused_argv)
{
VSTRING *unquoted = vstring_alloc(BUFLEN);
VSTRING *quoted = vstring_alloc(100);
ssize_t len;
/*
* Negative tests.
*/
if (xtext_unquote(unquoted, "++1") != 0)
msg_warn("undetected error pattern 1");
if (xtext_unquote(unquoted, "+2+") != 0)
msg_warn("undetected error pattern 2");
/*
* Positive tests.
*/
while ((len = read_buf(VSTREAM_IN, unquoted)) > 0) {
xtext_quote(quoted, STR(unquoted), "+=");
if (xtext_unquote(unquoted, STR(quoted)) == 0)
msg_fatal("bad input: %.100s", STR(quoted));
if (LEN(unquoted) != len)
msg_fatal("len %ld != unquoted len %ld",
(long) len, (long) LEN(unquoted));
if (vstream_fwrite(VSTREAM_OUT, STR(unquoted), LEN(unquoted)) != LEN(unquoted))
msg_fatal("write error: %m");
}
vstream_fflush(VSTREAM_OUT);
vstring_free(unquoted);
vstring_free(quoted);
return (0);
}
#endif
|
