Copyright updates:
[exim.git] / src / src / transports / queuefile.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) Andrew Colin Kissa <andrew@topdog.za.net> 2016 */
6 /* Copyright (c) University of Cambridge 2016 */
7 /* Copyright (c) The Exim Maintainers 1995 - 2020 */
8 /* See the file NOTICE for conditions of use and distribution. */
9
10
11 #include "../exim.h"
12 #include "queuefile.h"
13
14 /* Options specific to the appendfile transport. They must be in alphabetic
15 order (note that "_" comes before the lower case letters). Some of them are
16 stored in the publicly visible instance block - these are flagged with the
17 opt_public flag. */
18
19 optionlist queuefile_transport_options[] = {
20 { "directory", opt_stringptr,
21 OPT_OFF(queuefile_transport_options_block, dirname) },
22 };
23
24
25 /* Size of the options list. An extern variable has to be used so that its
26 address can appear in the tables drtables.c. */
27
28 int queuefile_transport_options_count =
29 sizeof(queuefile_transport_options) / sizeof(optionlist);
30
31
32 #ifdef MACRO_PREDEF
33
34 /* Dummy values */
35 queuefile_transport_options_block queuefile_transport_option_defaults = {0};
36 void queuefile_transport_init(transport_instance *tblock) {}
37 BOOL queuefile_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
38
39 #else /*!MACRO_PREDEF*/
40
41
42
43 /* Default private options block for the appendfile transport. */
44
45 queuefile_transport_options_block queuefile_transport_option_defaults = {
46 NULL, /* dirname */
47 };
48
49 /*************************************************
50 * Initialization entry point *
51 *************************************************/
52
53 void queuefile_transport_init(transport_instance *tblock)
54 {
55 queuefile_transport_options_block *ob =
56 (queuefile_transport_options_block *) tblock->options_block;
57
58 if (!ob->dirname)
59 log_write(0, LOG_PANIC_DIE | LOG_CONFIG,
60 "directory must be set for the %s transport", tblock->name);
61 }
62
63 /* This function will copy from a file to another
64
65 Arguments:
66 dst fd to write to (the destination queue file)
67 src fd to read from (the spool queue file)
68
69 Returns: TRUE if all went well, FALSE otherwise with errno set
70 */
71
72 static BOOL
73 copy_spool_file(int dst, int src)
74 {
75 int i, j;
76 uschar buffer[16384];
77
78 if (lseek(src, 0, SEEK_SET) != 0)
79 return FALSE;
80
81 do
82 if ((j = read(src, buffer, sizeof(buffer))) > 0)
83 for (uschar * s = buffer; (i = write(dst, s, j)) != j; s += i, j -= i)
84 if (i < 0)
85 return FALSE;
86 else if (j < 0)
87 return FALSE;
88 while (j > 0);
89 return TRUE;
90 }
91
92 /* This function performs the actual copying of the header
93 and data files to the destination directory
94
95 Arguments:
96 tb the transport block
97 addr address_item being processed
98 dstpath destination directory name
99 sdfd int Source directory fd
100 ddfd int Destination directory fd
101 link_file BOOL use linkat instead of data copy
102 srcfd fd for data file, or -1 for header file
103
104 Returns: TRUE if all went well, FALSE otherwise
105 */
106
107 static BOOL
108 copy_spool_files(transport_instance * tb, address_item * addr,
109 const uschar * dstpath, int sdfd, int ddfd, BOOL link_file, int srcfd)
110 {
111 BOOL is_hdr_file = srcfd < 0;
112 const uschar * suffix = srcfd < 0 ? US"H" : US"D";
113 int dstfd;
114 const uschar * filename = string_sprintf("%s-%s", message_id, suffix);
115 const uschar * srcpath = spool_fname(US"input", message_subdir, message_id, suffix);
116 const uschar * s, * op;
117
118 dstpath = string_sprintf("%s/%s-%s", dstpath, message_id, suffix);
119
120 if (link_file)
121 {
122 DEBUG(D_transport) debug_printf("%s transport, linking %s => %s\n",
123 tb->name, srcpath, dstpath);
124
125 if (linkat(sdfd, CCS filename, ddfd, CCS filename, 0) >= 0)
126 return TRUE;
127
128 op = US"linking";
129 s = dstpath;
130 }
131 else /* use data copy */
132 {
133 DEBUG(D_transport) debug_printf("%s transport, copying %s => %s\n",
134 tb->name, srcpath, dstpath);
135
136 if ( (s = dstpath,
137 (dstfd = exim_openat4(ddfd, CCS filename, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE))
138 < 0
139 )
140 || is_hdr_file
141 && (s = srcpath, (srcfd = exim_openat(sdfd, CCS filename, O_RDONLY)) < 0)
142 )
143 op = US"opening";
144
145 else
146 if (s = dstpath, fchmod(dstfd, SPOOL_MODE) != 0)
147 op = US"setting perms on";
148 else
149 if (!copy_spool_file(dstfd, srcfd))
150 op = US"creating";
151 else
152 return TRUE;
153 }
154
155 addr->basic_errno = errno;
156 addr->message = string_sprintf("%s transport %s file: %s failed with error: %s",
157 tb->name, op, s, strerror(errno));
158 addr->transport_return = DEFER;
159 return FALSE;
160 }
161
162 /*************************************************
163 * Main entry point *
164 *************************************************/
165
166 /* This transport always returns FALSE, indicating that the status in
167 the first address is the status for all addresses in a batch. */
168
169 BOOL
170 queuefile_transport_entry(transport_instance * tblock, address_item * addr)
171 {
172 queuefile_transport_options_block * ob =
173 (queuefile_transport_options_block *) tblock->options_block;
174 BOOL can_link;
175 uschar * sourcedir = spool_dname(US"input", message_subdir);
176 uschar * s, * dstdir;
177 struct stat dstatbuf, sstatbuf;
178 int ddfd = -1, sdfd = -1;
179
180 DEBUG(D_transport)
181 debug_printf("%s transport entered\n", tblock->name);
182
183 #ifndef O_DIRECTORY
184 # define O_DIRECTORY 0
185 #endif
186 #ifndef O_NOFOLLOW
187 # define O_NOFOLLOW 0
188 #endif
189
190 if (!(dstdir = expand_string(ob->dirname)))
191 {
192 addr->message = string_sprintf("%s transport: failed to expand dirname option",
193 tblock->name);
194 addr->transport_return = DEFER;
195 return FALSE;
196 }
197 if (*dstdir != '/')
198 {
199 addr->transport_return = PANIC;
200 addr->message = string_sprintf("%s transport directory: "
201 "%s is not absolute", tblock->name, dstdir);
202 return FALSE;
203 }
204
205 /* Open the source and destination directories and check if they are
206 on the same filesystem, so we can hard-link files rather than copying. */
207
208 if ( (s = dstdir,
209 (ddfd = Uopen(s, O_RDONLY | O_DIRECTORY | O_NOFOLLOW, 0)) < 0)
210 || (s = sourcedir,
211 (sdfd = Uopen(sourcedir, O_RDONLY | O_DIRECTORY | O_NOFOLLOW, 0)) < 0)
212 )
213 {
214 addr->transport_return = PANIC;
215 addr->basic_errno = errno;
216 addr->message = string_sprintf("%s transport accessing directory: %s "
217 "failed with error: %s", tblock->name, s, strerror(errno));
218 if (ddfd >= 0) (void) close(ddfd);
219 return FALSE;
220 }
221
222 if ( (s = dstdir, fstat(ddfd, &dstatbuf) < 0)
223 || (s = sourcedir, fstat(sdfd, &sstatbuf) < 0)
224 )
225 {
226 addr->transport_return = PANIC;
227 addr->basic_errno = errno;
228 addr->message = string_sprintf("%s transport fstat on directory fd: "
229 "%s failed with error: %s", tblock->name, s, strerror(errno));
230 goto RETURN;
231 }
232 can_link = (dstatbuf.st_dev == sstatbuf.st_dev);
233
234 if (f.dont_deliver)
235 {
236 DEBUG(D_transport)
237 debug_printf("*** delivery by %s transport bypassed by -N option\n",
238 tblock->name);
239 addr->transport_return = OK;
240 goto RETURN;
241 }
242
243 /* Link or copy the header and data spool files */
244
245 DEBUG(D_transport)
246 debug_printf("%s transport, copying header file\n", tblock->name);
247
248 if (!copy_spool_files(tblock, addr, dstdir, sdfd, ddfd, can_link, -1))
249 goto RETURN;
250
251 DEBUG(D_transport)
252 debug_printf("%s transport, copying data file\n", tblock->name);
253
254 if (!copy_spool_files(tblock, addr, dstdir, sdfd, ddfd, can_link,
255 deliver_datafile))
256 {
257 DEBUG(D_transport)
258 debug_printf("%s transport, copying data file failed, "
259 "unlinking the header file\n", tblock->name);
260 Uunlink(string_sprintf("%s/%s-H", dstdir, message_id));
261 goto RETURN;
262 }
263
264 DEBUG(D_transport)
265 debug_printf("%s transport succeeded\n", tblock->name);
266
267 addr->transport_return = OK;
268
269 RETURN:
270 if (ddfd >= 0) (void) close(ddfd);
271 if (sdfd >= 0) (void) close(sdfd);
272
273 /* A return of FALSE means that if there was an error, a common error was
274 put in the first address of a batch. */
275 return FALSE;
276 }
277
278 #endif /*!MACRO_PREDEF*/