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
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
/*++
/* NAME
/* smtpd_token 3
/* SUMMARY
/* tokenize SMTPD command
/* SYNOPSIS
/* #include <smtpd_token.h>
/*
/* typedef struct {
/* .in +4
/* int tokval;
/* char *strval;
/* /* other stuff... */
/* .in -4
/* } SMTPD_TOKEN;
/*
/* int smtpd_token(str, argvp)
/* char *str;
/* SMTPD_TOKEN **argvp;
/* DESCRIPTION
/* smtpd_token() routine converts the string in \fIstr\fR to an
/* array of tokens in \fIargvp\fR. The number of tokens is returned
/* via the function return value.
/*
/* Token types:
/* .IP SMTPD_TOK_OTHER
/* The token is something else.
/* .IP SMTPD_TOK_ERROR
/* A malformed token.
/* BUGS
/* This tokenizer understands just enough to tokenize SMTPD commands.
/* It understands backslash escapes, white space, quoted strings,
/* and addresses (including quoted text) enclosed by < and >.
/* The input is broken up into tokens by whitespace, except for
/* whitespace that is protected by quotes etc.
/* 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
/*--*/
/* System library. */
#include <sys_defs.h>
#include <ctype.h>
#include <string.h>
#include <unistd.h>
#ifdef STRCASECMP_IN_STRINGS_H
#include <strings.h>
#endif
/* Utility library. */
#include <mymalloc.h>
#include <mvect.h>
/* Application-specific. */
#include "smtpd_token.h"
/* smtp_quoted - read until closing quote */
static char *smtp_quoted(char *cp, SMTPD_TOKEN *arg, int start, int last)
{
static VSTRING *stack;
int wanted;
int c;
/*
* Parser stack. `ch' is always the most-recently entered character.
*/
#define ENTER_CHAR(buf, ch) VSTRING_ADDCH(buf, ch);
#define LEAVE_CHAR(buf, ch) { \
vstring_truncate(buf, VSTRING_LEN(buf) - 1); \
ch = vstring_end(buf)[-1]; \
}
if (stack == 0)
stack = vstring_alloc(1);
VSTRING_RESET(stack);
ENTER_CHAR(stack, wanted = last);
VSTRING_ADDCH(arg->vstrval, start);
for (;;) {
if ((c = *cp) == 0)
break;
cp++;
VSTRING_ADDCH(arg->vstrval, c);
if (c == '\\') { /* parse escape sequence */
if ((c = *cp) == 0)
break;
cp++;
VSTRING_ADDCH(arg->vstrval, c);
} else if (c == wanted) { /* closing quote etc. */
if (VSTRING_LEN(stack) == 1)
return (cp);
LEAVE_CHAR(stack, wanted);
} else if (c == '"') {
ENTER_CHAR(stack, wanted = '"'); /* highest precedence */
} else if (c == '<' && wanted == '>') {
ENTER_CHAR(stack, wanted = '>'); /* lowest precedence */
}
}
arg->tokval = SMTPD_TOK_ERROR; /* missing end */
return (cp);
}
/* smtp_next_token - extract next token from input, update cp */
static char *smtp_next_token(char *cp, SMTPD_TOKEN *arg)
{
int c;
VSTRING_RESET(arg->vstrval);
arg->tokval = SMTPD_TOK_OTHER;
#define STR(x) vstring_str(x)
#define LEN(x) VSTRING_LEN(x)
#define STREQ(x,y,l) (strncasecmp((x), (y), (l)) == 0)
for (;;) {
if ((c = *cp) == 0) /* end of input */
break;
cp++;
if (ISSPACE(c)) { /* whitespace, skip */
while (*cp && ISSPACE(*cp))
cp++;
if (LEN(arg->vstrval) > 0) /* end of token */
break;
} else if (c == '<') { /* <stuff> */
cp = smtp_quoted(cp, arg, c, '>');
} else if (c == '"') { /* "stuff" */
cp = smtp_quoted(cp, arg, c, c);
} else if (c == ':') { /* this is gross, but... */
VSTRING_ADDCH(arg->vstrval, c);
if (STREQ(STR(arg->vstrval), "to:", LEN(arg->vstrval))
|| STREQ(STR(arg->vstrval), "from:", LEN(arg->vstrval)))
break;
} else { /* other */
if (c == '\\') {
VSTRING_ADDCH(arg->vstrval, c);
if ((c = *cp) == 0)
break;
cp++;
}
VSTRING_ADDCH(arg->vstrval, c);
}
}
if (LEN(arg->vstrval) <= 0) /* no token found */
return (0);
VSTRING_TERMINATE(arg->vstrval);
arg->strval = vstring_str(arg->vstrval);
return (cp);
}
/* smtpd_token_init - initialize token structures */
static void smtpd_token_init(char *ptr, ssize_t count)
{
SMTPD_TOKEN *arg;
int n;
for (arg = (SMTPD_TOKEN *) ptr, n = 0; n < count; arg++, n++)
arg->vstrval = vstring_alloc(10);
}
/* smtpd_token - tokenize SMTPD command */
int smtpd_token(char *cp, SMTPD_TOKEN **argvp)
{
static SMTPD_TOKEN *smtp_argv;
static MVECT mvect;
int n;
if (smtp_argv == 0)
smtp_argv = (SMTPD_TOKEN *) mvect_alloc(&mvect, sizeof(*smtp_argv), 1,
smtpd_token_init, (MVECT_FN) 0);
for (n = 0; /* void */ ; n++) {
smtp_argv = (SMTPD_TOKEN *) mvect_realloc(&mvect, n + 1);
if ((cp = smtp_next_token(cp, smtp_argv + n)) == 0)
break;
}
*argvp = smtp_argv;
return (n);
}
#ifdef TEST
/*
* Test program for the SMTPD command tokenizer.
*/
#include <stdlib.h>
#include <vstream.h>
#include <vstring_vstream.h>
int main(int unused_argc, char **unused_argv)
{
VSTRING *vp = vstring_alloc(10);
int tok_argc;
SMTPD_TOKEN *tok_argv;
int i;
for (;;) {
if (isatty(STDIN_FILENO))
vstream_printf("enter SMTPD command: ");
vstream_fflush(VSTREAM_OUT);
if (vstring_get_nonl(vp, VSTREAM_IN) == VSTREAM_EOF)
break;
if (*vstring_str(vp) == '#')
continue;
if (!isatty(STDIN_FILENO))
vstream_printf("%s\n", vstring_str(vp));
tok_argc = smtpd_token(vstring_str(vp), &tok_argv);
for (i = 0; i < tok_argc; i++) {
vstream_printf("Token type: %s\n",
tok_argv[i].tokval == SMTPD_TOK_OTHER ? "other" :
tok_argv[i].tokval == SMTPD_TOK_ERROR ? "error" :
"unknown");
vstream_printf("Token value: %s\n", tok_argv[i].strval);
}
}
vstring_free(vp);
exit(0);
}
#endif
|
