1 /* 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 source tree.
8 */
9 #include "libbb.h"
10 #include "mail.h"
11
kill_helper(void)12 static void kill_helper(void)
13 {
14 if (G.helper_pid > 0) {
15 kill(G.helper_pid, SIGTERM);
16 G.helper_pid = 0;
17 }
18 }
19
20 // generic signal handler
signal_handler(int signo)21 static 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
30 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));
33 if (WIFEXITED(err)) {
34 G.helper_pid = 0;
35 if (WEXITSTATUS(err))
36 bb_error_msg_and_die("helper exited (%u)", WEXITSTATUS(err));
37 }
38 }
39 #undef err
40 }
41
launch_helper(const char ** argv)42 void FAST_FUNC launch_helper(const char **argv)
43 {
44 // setup vanilla unidirectional pipes interchange
45 int i;
46 int pipes[4];
47
48 xpipe(pipes);
49 xpipe(pipes + 2);
50
51 // NB: handler must be installed before vfork
52 bb_signals(0
53 + (1 << SIGCHLD)
54 + (1 << SIGALRM)
55 , signal_handler);
56
57 G.helper_pid = xvfork();
58
59 i = (!G.helper_pid) * 2; // for parent:0, for child:2
60 close(pipes[i + 1]); // 1 or 3 - closing one write end
61 close(pipes[2 - i]); // 2 or 0 - closing one read end
62 xmove_fd(pipes[i], STDIN_FILENO); // 0 or 2 - using other read end
63 xmove_fd(pipes[3 - i], STDOUT_FILENO); // 3 or 1 - using other write end
64 // End result:
65 // parent stdout [3] -> child stdin [2]
66 // child stdout [1] -> parent stdin [0]
67
68 if (!G.helper_pid) {
69 // child: try to execute connection helper
70 // NB: SIGCHLD & SIGALRM revert to SIG_DFL on exec
71 BB_EXECVP_or_die((char**)argv);
72 }
73
74 // parent
75 // check whether child is alive
76 //redundant:signal_handler(SIGCHLD);
77 // child seems OK -> parent goes on
78 atexit(kill_helper);
79 }
80
send_mail_command(const char * fmt,const char * param)81 char* FAST_FUNC send_mail_command(const char *fmt, const char *param)
82 {
83 char *msg;
84 if (timeout)
85 alarm(timeout);
86 msg = (char*)fmt;
87 if (fmt) {
88 msg = xasprintf(fmt, param);
89 if (verbose)
90 bb_error_msg("send:'%s'", msg);
91 printf("%s\r\n", msg);
92 }
93 fflush_all();
94 return msg;
95 }
96
97 // NB: parse_url can modify url[] (despite const), but only if '@' is there
98 /*
99 static char* FAST_FUNC parse_url(char *url, char **user, char **pass)
100 {
101 // parse [user[:pass]@]host
102 // return host
103 char *s = strchr(url, '@');
104 *user = *pass = NULL;
105 if (s) {
106 *s++ = '\0';
107 *user = url;
108 url = s;
109 s = strchr(*user, ':');
110 if (s) {
111 *s++ = '\0';
112 *pass = s;
113 }
114 }
115 return url;
116 }
117 */
118
encode_base64(char * fname,const char * text,const char * eol)119 void FAST_FUNC encode_base64(char *fname, const char *text, const char *eol)
120 {
121 enum {
122 SRC_BUF_SIZE = 57, /* This *MUST* be a multiple of 3 */
123 DST_BUF_SIZE = 4 * ((SRC_BUF_SIZE + 2) / 3),
124 };
125 #define src_buf text
126 char src[SRC_BUF_SIZE];
127 FILE *fp = fp;
128 ssize_t len = len;
129 char dst_buf[DST_BUF_SIZE + 1];
130
131 if (fname) {
132 fp = (NOT_LONE_DASH(fname)) ? xfopen_for_read(fname) : (FILE *)text;
133 src_buf = src;
134 } else if (text) {
135 // though we do not call uuencode(NULL, NULL) explicitly
136 // still we do not want to break things suddenly
137 len = strlen(text);
138 } else
139 return;
140
141 while (1) {
142 size_t size;
143 if (fname) {
144 size = fread((char *)src_buf, 1, SRC_BUF_SIZE, fp);
145 if ((ssize_t)size < 0)
146 bb_perror_msg_and_die(bb_msg_read_error);
147 } else {
148 size = len;
149 if (len > SRC_BUF_SIZE)
150 size = SRC_BUF_SIZE;
151 }
152 if (!size)
153 break;
154 // encode the buffer we just read in
155 bb_uuencode(dst_buf, src_buf, size, bb_uuenc_tbl_base64);
156 if (fname) {
157 puts(eol);
158 } else {
159 src_buf += size;
160 len -= size;
161 }
162 fwrite(dst_buf, 1, 4 * ((size + 2) / 3), stdout);
163 }
164 if (fname && NOT_LONE_DASH(fname))
165 fclose(fp);
166 #undef src_buf
167 }
168
169 /*
170 * get username and password from a file descriptor
171 */
get_cred_or_die(int fd)172 void FAST_FUNC get_cred_or_die(int fd)
173 {
174 if (isatty(fd)) {
175 G.user = xstrdup(bb_ask(fd, /* timeout: */ 0, "User: "));
176 G.pass = xstrdup(bb_ask(fd, /* timeout: */ 0, "Password: "));
177 } else {
178 G.user = xmalloc_reads(fd, /* maxsize: */ NULL);
179 G.pass = xmalloc_reads(fd, /* maxsize: */ NULL);
180 }
181 if (!G.user || !*G.user || !G.pass)
182 bb_error_msg_and_die("no username or password");
183 }
184