1 /* $NetBSD: dict_file.c,v 1.3 2022/10/08 16:12:50 christos Exp $ */
2
3 /*++
4 /* NAME
5 /* dict_file_to_buf 3
6 /* SUMMARY
7 /* include content from file as blob
8 /* SYNOPSIS
9 /* #include <dict.h>
10 /*
11 /* VSTRING *dict_file_to_buf(
12 /* DICT *dict,
13 /* const char *pathnames)
14 /*
15 /* VSTRING *dict_file_to_b64(
16 /* DICT *dict,
17 /* const char *pathnames)
18 /*
19 /* VSTRING *dict_file_from_b64(
20 /* DICT *dict,
21 /* const char *value)
22 /*
23 /* char *dict_file_get_error(
24 /* DICT *dict)
25 /*
26 /* void dict_file_purge_buffers(
27 /* DICT *dict)
28 /*
29 /* const char *dict_file_lookup(
30 /* DICT *dict)
31 /* DESCRIPTION
32 /* dict_file_to_buf() reads the content of the specified files,
33 /* with names separated by CHARS_COMMA_SP, while inserting a
34 /* gratuitous newline character between files. It returns a
35 /* pointer to a buffer which is owned by the DICT, or a null
36 /* pointer in case of error.
37 /*
38 /* dict_file_to_b64() invokes dict_file_to_buf() and converts
39 /* the result to base64. It returns a pointer to a buffer which
40 /* is owned by the DICT, or a null pointer in case of error.
41 /*
42 /* dict_file_from_b64() converts a value from base64. It returns
43 /* a pointer to a buffer which is owned by the DICT, or a null
44 /* pointer in case of error.
45 /*
46 /* dict_file_purge_buffers() disposes of dict_file-related
47 /* memory that are associated with this DICT.
48 /*
49 /* dict_file_get_error() should be called only after error;
50 /* it returns a description of the problem. Storage is owned
51 /* by the caller.
52 /*
53 /* dict_file_lookup() wraps the dictionary lookup method and
54 /* decodes the base64 lookup result. The dictionary must be
55 /* opened with DICT_FLAG_SRC_RHS_IS_FILE. Sets dict->error to
56 /* DICT_ERR_CONFIG if the content is invalid. Decoding is not
57 /* built into the dict->lookup() method, because that would
58 /* complicate the implementation of map nesting (inline, thash),
59 /* map composition (pipemap, unionmap), and map proxying.
60 /* DIAGNOSTICS
61 /* Panic: interface violation.
62 /*
63 /* In case of error the VSTRING result value is a null pointer, and
64 /* an error description can be retrieved with dict_file_get_error().
65 /* The storage is owned by the caller.
66 /* LICENSE
67 /* .ad
68 /* .fi
69 /* The Secure Mailer license must be distributed with this software.
70 /* AUTHOR(S)
71 /* Wietse Venema
72 /* Google, Inc.
73 /* 111 8th Avenue
74 /* New York, NY 10011, USA
75 /*--*/
76
77 /*
78 * System library.
79 */
80 #include <sys_defs.h>
81 #include <sys/stat.h>
82 #include <string.h>
83
84 /*
85 * Utility library.
86 */
87 #include <base64_code.h>
88 #include <dict.h>
89 #include <msg.h>
90 #include <mymalloc.h>
91 #include <vstream.h>
92 #include <vstring.h>
93
94 /*
95 * SLMs.
96 */
97 #define STR(x) vstring_str(x)
98 #define LEN(x) VSTRING_LEN(x)
99
100 /* dict_file_to_buf - read files into a buffer */
101
dict_file_to_buf(DICT * dict,const char * pathnames)102 VSTRING *dict_file_to_buf(DICT *dict, const char *pathnames)
103 {
104 struct stat st;
105 VSTREAM *fp = 0;
106 ARGV *argv;
107 char **cpp;
108
109 /* dict_file_to_buf() postcondition: dict->file_buf exists. */
110 if (dict->file_buf == 0)
111 dict->file_buf = vstring_alloc(100);
112
113 #define DICT_FILE_RETURN(retval) do { \
114 argv_free(argv); \
115 if (fp) vstream_fclose(fp); \
116 return (retval); \
117 } while (0);
118
119 argv = argv_split(pathnames, CHARS_COMMA_SP);
120 if (argv->argc == 0) {
121 vstring_sprintf(dict->file_buf, "empty pathname list: >>%s<<'",
122 pathnames);
123 DICT_FILE_RETURN(0);
124 }
125 VSTRING_RESET(dict->file_buf);
126 for (cpp = argv->argv; *cpp; cpp++) {
127 if ((fp = vstream_fopen(*cpp, O_RDONLY, 0)) == 0
128 || fstat(vstream_fileno(fp), &st) < 0) {
129 vstring_sprintf(dict->file_buf, "open %s: %m", *cpp);
130 DICT_FILE_RETURN(0);
131 }
132 if (st.st_size > SSIZE_T_MAX - LEN(dict->file_buf)) {
133 vstring_sprintf(dict->file_buf, "file too large: %s", pathnames);
134 DICT_FILE_RETURN(0);
135 }
136 if (vstream_fread_app(fp, dict->file_buf, st.st_size) != st.st_size) {
137 vstring_sprintf(dict->file_buf, "read %s: %m", *cpp);
138 DICT_FILE_RETURN(0);
139 }
140 (void) vstream_fclose(fp);
141 fp = 0;
142 if (cpp[1] != 0)
143 VSTRING_ADDCH(dict->file_buf, '\n');
144 }
145 VSTRING_TERMINATE(dict->file_buf);
146 DICT_FILE_RETURN(dict->file_buf);
147 }
148
149 /* dict_file_to_b64 - read files into a base64-encoded buffer */
150
dict_file_to_b64(DICT * dict,const char * pathnames)151 VSTRING *dict_file_to_b64(DICT *dict, const char *pathnames)
152 {
153 ssize_t helper;
154
155 if (dict_file_to_buf(dict, pathnames) == 0)
156 return (0);
157 if (dict->file_b64 == 0)
158 dict->file_b64 = vstring_alloc(100);
159 helper = (LEN(dict->file_buf) + 2) / 3;
160 if (helper > SSIZE_T_MAX / 4) {
161 vstring_sprintf(dict->file_buf, "file too large: %s", pathnames);
162 return (0);
163 }
164 VSTRING_RESET(dict->file_b64);
165 VSTRING_SPACE(dict->file_b64, helper * 4);
166 return (base64_encode(dict->file_b64, STR(dict->file_buf),
167 LEN(dict->file_buf)));
168 }
169
170 /* dict_file_from_b64 - convert value from base64 */
171
dict_file_from_b64(DICT * dict,const char * value)172 VSTRING *dict_file_from_b64(DICT *dict, const char *value)
173 {
174 ssize_t helper;
175 VSTRING *result;
176
177 if (dict->file_buf == 0)
178 dict->file_buf = vstring_alloc(100);
179 helper = strlen(value) / 4;
180 VSTRING_RESET(dict->file_buf);
181 VSTRING_SPACE(dict->file_buf, helper * 3);
182 result = base64_decode(dict->file_buf, value, strlen(value));
183 if (result == 0)
184 vstring_sprintf(dict->file_buf, "malformed BASE64 value: %.30s", value);
185 return (result);
186 }
187
188 /* dict_file_get_error - return error text */
189
dict_file_get_error(DICT * dict)190 char *dict_file_get_error(DICT *dict)
191 {
192 if (dict->file_buf == 0)
193 msg_panic("dict_file_get_error: no buffer");
194 return (mystrdup(STR(dict->file_buf)));
195 }
196
197 /* dict_file_purge_buffers - purge file buffers */
198
dict_file_purge_buffers(DICT * dict)199 void dict_file_purge_buffers(DICT *dict)
200 {
201 if (dict->file_buf) {
202 vstring_free(dict->file_buf);
203 dict->file_buf = 0;
204 }
205 if (dict->file_b64) {
206 vstring_free(dict->file_b64);
207 dict->file_b64 = 0;
208 }
209 }
210
211 /* dict_file_lookup - look up and decode dictionary entry */
212
dict_file_lookup(DICT * dict,const char * key)213 const char *dict_file_lookup(DICT *dict, const char *key)
214 {
215 const char myname[] = "dict_file_lookup";
216 const char *res;
217 VSTRING *unb64;
218 char *err;
219
220 if ((dict->flags & DICT_FLAG_SRC_RHS_IS_FILE) == 0)
221 msg_panic("%s: dictionary opened without DICT_FLAG_SRC_RHS_IS_FILE",
222 myname);
223 if ((res = dict->lookup(dict, key)) == 0)
224 return (0);
225 if ((unb64 = dict_file_from_b64(dict, res)) == 0) {
226 err = dict_file_get_error(dict);
227 msg_warn("table %s:%s: key %s: %s", dict->type, dict->name, key, err);
228 myfree(err);
229 dict->error = DICT_ERR_CONFIG;
230 return (0);
231 }
232 return STR(unb64);
233 }
234