1 /* getsubopt.c --- Parse comma separate list into words, DIGEST-MD5 style.
2  * Copyright (C) 2002-2021 Simon Josefsson
3  * Copyright (C) 1996, 1997, 1999 Free Software Foundation, Inc.
4  * From the GNU C Library, under GNU LGPL version 2.1.
5  * Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
6  * Modified for Libgsasl by Simon Josefsson <simon@josefsson.org>
7  *
8  * This file is part of GNU SASL Library.
9  *
10  * GNU SASL Library is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public License
12  * as published by the Free Software Foundation; either version 2.1 of
13  * the License, or (at your option) any later version.
14  *
15  * GNU SASL Library is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with GNU SASL Library; if not, write to the Free
22  * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
23  * Boston, MA 02110-1301, USA.
24  *
25  */
26 
27 #ifdef HAVE_CONFIG_H
28 #include "config.h"
29 #endif
30 
31 /* Get prototypes. */
32 #include "parser.h"
33 
34 /* Get memchr and memcmp. */
35 #include <string.h>
36 
37 /* Parse comma separated suboption from *OPTIONP and match against
38    strings in TOKENS.  If found return index and set *VALUEP to
39    optional value introduced by an equal sign.  If the suboption is
40    not part of TOKENS return in *VALUEP beginning of unknown
41    suboption.  On exit *OPTIONP is set to the beginning of the next
42    token or at the terminating NUL character.
43 
44    This function is NOT identical to standard getsubopt! */
45 int
digest_md5_getsubopt(char ** optionp,const char * const * tokens,char ** valuep)46 digest_md5_getsubopt (char **optionp,
47 		      const char *const *tokens, char **valuep)
48 {
49   char *endp, *vstart;
50   int cnt;
51   int inside_quote = 0;
52 
53   if (**optionp == '\0')
54     return -1;
55 
56   /* Find end of next token.  */
57   endp = *optionp;
58   while (*endp != '\0' && (inside_quote || (!inside_quote && *endp != ',')))
59     {
60       if (*endp == '"')
61 	inside_quote = !inside_quote;
62       endp++;
63     }
64 
65   /* Find start of value.  */
66   vstart = memchr (*optionp, '=', endp - *optionp);
67   if (vstart == NULL)
68     vstart = endp;
69 
70   /* Try to match the characters between *OPTIONP and VSTART against
71      one of the TOKENS.  */
72   for (cnt = 0; tokens[cnt] != NULL; ++cnt)
73     if (memcmp (*optionp, tokens[cnt], vstart - *optionp) == 0
74 	&& tokens[cnt][vstart - *optionp] == '\0')
75       {
76 	/* We found the current option in TOKENS.  */
77 	*valuep = vstart != endp ? vstart + 1 : NULL;
78 
79 	while (*valuep && (**valuep == ' ' ||
80 			   **valuep == '\t' ||
81 			   **valuep == '\r' ||
82 			   **valuep == '\n' || **valuep == '"'))
83 	  (*valuep)++;
84 
85 	if (*endp != '\0')
86 	  {
87 	    *endp = '\0';
88 	    *optionp = endp + 1;
89 	  }
90 	else
91 	  *optionp = endp;
92 	endp--;
93 	while (*endp == ' ' ||
94 	       *endp == '\t' ||
95 	       *endp == '\r' || *endp == '\n' || *endp == '"')
96 	  *endp-- = '\0';
97 	while (**optionp == ' ' ||
98 	       **optionp == '\t' || **optionp == '\r' || **optionp == '\n')
99 	  (*optionp)++;
100 
101 	return cnt;
102       }
103 
104   /* The current suboption does not match any option.  */
105   *valuep = *optionp;
106 
107   if (*endp != '\0')
108     *endp++ = '\0';
109   *optionp = endp;
110   while (**optionp == ' ' ||
111 	 **optionp == '\t' || **optionp == '\r' || **optionp == '\n')
112     (*optionp)++;
113 
114   return -1;
115 }
116