blob: 68883ff42c030097ceed6ac96d09cb14758873dd [file] [log] [blame]
Denis Vlasenko239d06b2008-11-06 23:42:42 +00001/* vi: set sw=4 ts=4: */
2/*
3 * helper routines
4 *
5 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
6 *
7 * Licensed under GPLv2, see file LICENSE in this tarball for details.
8 */
9#include "libbb.h"
10#include "mail.h"
11
12static void kill_helper(void)
13{
Denis Vlasenko021de3f2009-03-04 17:56:00 +000014 if (G.helper_pid > 0) {
Denis Vlasenko239d06b2008-11-06 23:42:42 +000015 kill(G.helper_pid, SIGTERM);
Denis Vlasenko021de3f2009-03-04 17:56:00 +000016 G.helper_pid = 0;
17 }
Denis Vlasenko239d06b2008-11-06 23:42:42 +000018}
19
20// generic signal handler
21static void signal_handler(int signo)
22{
23#define err signo
24 if (SIGALRM == signo) {
25 kill_helper();
26 bb_error_msg_and_die("timed out");
27 }
28
29 // SIGCHLD. reap zombies
Denis Vlasenko021de3f2009-03-04 17:56:00 +000030 if (safe_waitpid(G.helper_pid, &err, WNOHANG) > 0) {
31 if (WIFSIGNALED(err))
32 bb_error_msg_and_die("helper killed by signal %u", WTERMSIG(err));
Denis Vlasenko239d06b2008-11-06 23:42:42 +000033 if (WIFEXITED(err)) {
34 G.helper_pid = 0;
35 if (WEXITSTATUS(err))
Denis Vlasenko021de3f2009-03-04 17:56:00 +000036 bb_error_msg_and_die("helper exited (%u)", WEXITSTATUS(err));
Denis Vlasenko239d06b2008-11-06 23:42:42 +000037 }
Denis Vlasenko021de3f2009-03-04 17:56:00 +000038 }
Denis Vlasenko239d06b2008-11-06 23:42:42 +000039#undef err
40}
41
42void FAST_FUNC launch_helper(const char **argv)
43{
44 // setup vanilla unidirectional pipes interchange
Denis Vlasenko021de3f2009-03-04 17:56:00 +000045 int i;
Denis Vlasenko239d06b2008-11-06 23:42:42 +000046 int pipes[4];
47
48 xpipe(pipes);
Denis Vlasenko021de3f2009-03-04 17:56:00 +000049 xpipe(pipes + 2);
50
Denis Vlasenko47741792009-03-10 16:01:57 +000051 // NB: handler must be installed before vfork
52 bb_signals(0
53 + (1 << SIGCHLD)
54 + (1 << SIGALRM)
55 , signal_handler);
56
Denis Vlasenko239d06b2008-11-06 23:42:42 +000057 G.helper_pid = vfork();
58 if (G.helper_pid < 0)
59 bb_perror_msg_and_die("vfork");
Denis Vlasenko021de3f2009-03-04 17:56:00 +000060
61 i = (!G.helper_pid) * 2; // for parent:0, for child:2
62 close(pipes[i + 1]); // 1 or 3 - closing one write end
63 close(pipes[2 - i]); // 2 or 0 - closing one read end
64 xmove_fd(pipes[i], STDIN_FILENO); // 0 or 2 - using other read end
65 xmove_fd(pipes[3 - i], STDOUT_FILENO); // 3 or 1 - other write end
66
Denis Vlasenko239d06b2008-11-06 23:42:42 +000067 if (!G.helper_pid) {
68 // child: try to execute connection helper
Denis Vlasenko47741792009-03-10 16:01:57 +000069 // NB: SIGCHLD & SIGALRM revert to SIG_DFL on exec
Denis Vlasenko239d06b2008-11-06 23:42:42 +000070 BB_EXECVP(*argv, (char **)argv);
71 _exit(127);
72 }
Denis Vlasenko021de3f2009-03-04 17:56:00 +000073
74 // parent
Denis Vlasenko021de3f2009-03-04 17:56:00 +000075 // check whether child is alive
76 //redundant:signal_handler(SIGCHLD);
Denis Vlasenko239d06b2008-11-06 23:42:42 +000077 // child seems OK -> parent goes on
78 atexit(kill_helper);
79}
80
81const FAST_FUNC char *command(const char *fmt, const char *param)
82{
83 const char *msg = fmt;
84 if (timeout)
85 alarm(timeout);
86 if (msg) {
87 msg = xasprintf(fmt, param);
88 printf("%s\r\n", msg);
89 }
90 fflush(stdout);
91 return msg;
92}
93
94// NB: parse_url can modify url[] (despite const), but only if '@' is there
95/*
96static char FAST_FUNC *parse_url(char *url, char **user, char **pass)
97{
98 // parse [user[:pass]@]host
99 // return host
100 char *s = strchr(url, '@');
101 *user = *pass = NULL;
102 if (s) {
103 *s++ = '\0';
104 *user = url;
105 url = s;
106 s = strchr(*user, ':');
107 if (s) {
108 *s++ = '\0';
109 *pass = s;
110 }
111 }
112 return url;
113}
114*/
115
116void FAST_FUNC encode_base64(char *fname, const char *text, const char *eol)
117{
118 enum {
119 SRC_BUF_SIZE = 45, /* This *MUST* be a multiple of 3 */
120 DST_BUF_SIZE = 4 * ((SRC_BUF_SIZE + 2) / 3),
121 };
122
123#define src_buf text
124 FILE *fp = fp;
125 ssize_t len = len;
126 char dst_buf[DST_BUF_SIZE + 1];
127
128 if (fname) {
129 fp = (NOT_LONE_DASH(fname)) ? xfopen_for_read(fname) : (FILE *)text;
130 src_buf = bb_common_bufsiz1;
131 // N.B. strlen(NULL) segfaults!
132 } else if (text) {
133 // though we do not call uuencode(NULL, NULL) explicitly
134 // still we do not want to break things suddenly
135 len = strlen(text);
136 } else
137 return;
138
139 while (1) {
140 size_t size;
141 if (fname) {
142 size = fread((char *)src_buf, 1, SRC_BUF_SIZE, fp);
143 if ((ssize_t)size < 0)
144 bb_perror_msg_and_die(bb_msg_read_error);
145 } else {
146 size = len;
147 if (len > SRC_BUF_SIZE)
148 size = SRC_BUF_SIZE;
149 }
150 if (!size)
151 break;
152 // encode the buffer we just read in
153 bb_uuencode(dst_buf, src_buf, size, bb_uuenc_tbl_base64);
154 if (fname) {
155 printf("%s\n", eol);
156 } else {
157 src_buf += size;
158 len -= size;
159 }
160 fwrite(dst_buf, 1, 4 * ((size + 2) / 3), stdout);
161 }
162 if (fname && NOT_LONE_DASH(fname))
163 fclose(fp);
164#undef src_buf
165}
166
167void FAST_FUNC decode_base64(FILE *src_stream, FILE *dst_stream)
168{
169 int term_count = 1;
170
171 while (1) {
172 char translated[4];
173 int count = 0;
174
175 while (count < 4) {
176 char *table_ptr;
177 int ch;
178
179 /* Get next _valid_ character.
180 * global vector bb_uuenc_tbl_base64[] contains this string:
181 * "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=\n"
182 */
183 do {
184 ch = fgetc(src_stream);
185 if (ch == EOF) {
186 bb_error_msg_and_die(bb_msg_read_error);
187 }
188 // - means end of MIME section
189 if ('-' == ch) {
190 // push it back
191 ungetc(ch, src_stream);
192 return;
193 }
194 table_ptr = strchr(bb_uuenc_tbl_base64, ch);
195 } while (table_ptr == NULL);
196
197 /* Convert encoded character to decimal */
198 ch = table_ptr - bb_uuenc_tbl_base64;
199
200 if (*table_ptr == '=') {
201 if (term_count == 0) {
202 translated[count] = '\0';
203 break;
204 }
205 term_count++;
206 } else if (*table_ptr == '\n') {
207 /* Check for terminating line */
208 if (term_count == 5) {
209 return;
210 }
211 term_count = 1;
212 continue;
213 } else {
214 translated[count] = ch;
215 count++;
216 term_count = 0;
217 }
218 }
219
220 /* Merge 6 bit chars to 8 bit */
221 if (count > 1) {
222 fputc(translated[0] << 2 | translated[1] >> 4, dst_stream);
223 }
224 if (count > 2) {
225 fputc(translated[1] << 4 | translated[2] >> 2, dst_stream);
226 }
227 if (count > 3) {
228 fputc(translated[2] << 6 | translated[3], dst_stream);
229 }
230 }
231}
232
233
234/*
235 * get username and password from a file descriptor
236 */
237void FAST_FUNC get_cred_or_die(int fd)
238{
Denis Vlasenko239d06b2008-11-06 23:42:42 +0000239 if (isatty(fd)) {
Denis Vlasenko021de3f2009-03-04 17:56:00 +0000240 G.user = xstrdup(bb_ask(fd, /* timeout: */ 0, "User: "));
241 G.pass = xstrdup(bb_ask(fd, /* timeout: */ 0, "Password: "));
Denis Vlasenko239d06b2008-11-06 23:42:42 +0000242 } else {
Denis Vlasenko021de3f2009-03-04 17:56:00 +0000243 G.user = xmalloc_reads(fd, /* pfx: */ NULL, /* maxsize: */ NULL);
244 G.pass = xmalloc_reads(fd, /* pfx: */ NULL, /* maxsize: */ NULL);
Denis Vlasenko239d06b2008-11-06 23:42:42 +0000245 }
Denis Vlasenko021de3f2009-03-04 17:56:00 +0000246 if (!G.user || !*G.user || !G.pass)
Denis Vlasenko239d06b2008-11-06 23:42:42 +0000247 bb_error_msg_and_die("no username or password");
248}