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 #if defined(__linux__)
10 # include <sys/prctl.h>
11 # define PRCTL
12 #elif defined(__FreeBSD__)
13 # include <sys/procctl.h>
14 # define PROCCTL
15 #endif
16 #include "libbb.h"
17 #include "mail.h"
18
19 // common signal handler
signal_handler(int signo)20 static void signal_handler(int signo)
21 {
22 if (SIGALRM == signo) {
23 bb_simple_error_msg_and_die("timed out");
24 }
25
26 // SIGCHLD. reap the zombie if we expect one
27 if (G.helper_pid == 0)
28 return;
29 #define status signo
30 if (safe_waitpid(G.helper_pid, &status, WNOHANG) > 0) {
31 G.helper_pid = 0;
32 if (WIFSIGNALED(status))
33 bb_error_msg_and_die("helper killed by signal %u", WTERMSIG(status));
34 if (WIFEXITED(status) && WEXITSTATUS(status) != 0)
35 bb_error_msg_and_die("helper exited (%u)", WEXITSTATUS(status));
36 }
37 #undef status
38 }
39
launch_helper(const char ** argv)40 void FAST_FUNC launch_helper(const char **argv)
41 {
42 pid_t pid;
43 struct fd_pair child_out;
44 struct fd_pair child_in;
45
46 xpiped_pair(child_out);
47 xpiped_pair(child_in);
48
49 // NB: handler must be installed before vfork
50 bb_signals(0
51 + (1 << SIGCHLD)
52 + (1 << SIGALRM)
53 , signal_handler);
54
55 fflush_all();
56 pid = xvfork();
57 if (pid == 0) {
58 // child
59 close(child_in.wr);
60 close(child_out.rd);
61 xmove_fd(child_in.rd, STDIN_FILENO);
62 xmove_fd(child_out.wr, STDOUT_FILENO);
63 // if parent dies, get SIGTERM
64 #if defined(PRCTL)
65 prctl(PR_SET_PDEATHSIG, SIGTERM, 0, 0, 0);
66 #elif defined(PROCCTL)
67 {
68 int signum = SIGTERM;
69 procctl(P_PID, 0, PROC_PDEATHSIG_CTL, &signum);
70 }
71 #endif
72 // try to execute connection helper
73 // NB: SIGCHLD & SIGALRM revert to SIG_DFL on exec
74 BB_EXECVP_or_die((char**)argv);
75 }
76 G.helper_pid = pid;
77 close(child_out.wr);
78 close(child_in.rd);
79 xmove_fd(child_out.rd, STDIN_FILENO);
80 xmove_fd(child_in.wr, STDOUT_FILENO);
81
82 // parent goes on
83 }
84
send_r_n(const char * s)85 void FAST_FUNC send_r_n(const char *s)
86 {
87 if (G.verbose)
88 bb_error_msg("send:'%s'", s);
89 printf("%s\r\n", s);
90 }
91
send_mail_command(const char * fmt,const char * param)92 char* FAST_FUNC send_mail_command(const char *fmt, const char *param)
93 {
94 char *msg;
95 if (G.timeout)
96 alarm(G.timeout);
97 msg = (char*)fmt;
98 if (fmt) {
99 msg = xasprintf(fmt, param);
100 send_r_n(msg);
101 }
102 fflush_all();
103 return msg;
104 }
105
106 // NB: parse_url can modify url[] (despite const), but only if '@' is there
107 /*
108 static char* FAST_FUNC parse_url(char *url, char **user, char **pass)
109 {
110 // parse [user[:pass]@]host
111 // return host
112 char *s = strchr(url, '@');
113 *user = *pass = NULL;
114 if (s) {
115 *s++ = '\0';
116 *user = url;
117 url = s;
118 s = strchr(*user, ':');
119 if (s) {
120 *s++ = '\0';
121 *pass = s;
122 }
123 }
124 return url;
125 }
126 */
127
encode_n_base64(const char * fname,const char * text,size_t len)128 static void encode_n_base64(const char *fname, const char *text, size_t len)
129 {
130 enum {
131 SRC_BUF_SIZE = 57, /* This *MUST* be a multiple of 3 */
132 DST_BUF_SIZE = 4 * ((SRC_BUF_SIZE + 2) / 3),
133 };
134 #define src_buf text
135 char src[SRC_BUF_SIZE];
136 FILE *fp = fp;
137 char dst_buf[DST_BUF_SIZE + 1];
138
139 if (fname) {
140 fp = (NOT_LONE_DASH(fname)) ? xfopen_for_read(fname) : stdin;
141 src_buf = src;
142 }
143
144 while (1) {
145 size_t size;
146 if (fname) {
147 size = fread((char *)src_buf, 1, SRC_BUF_SIZE, fp);
148 if ((ssize_t)size < 0)
149 bb_simple_perror_msg_and_die(bb_msg_read_error);
150 } else {
151 size = len;
152 if (len > SRC_BUF_SIZE)
153 size = SRC_BUF_SIZE;
154 }
155 if (!size)
156 break;
157 // encode the buffer we just read in
158 bb_uuencode(dst_buf, src_buf, size, bb_uuenc_tbl_base64);
159 if (fname) {
160 puts("");
161 } else {
162 src_buf += size;
163 len -= size;
164 }
165 fwrite(dst_buf, 1, 4 * ((size + 2) / 3), stdout);
166 }
167 if (fname && NOT_LONE_DASH(fname))
168 fclose(fp);
169 #undef src_buf
170 }
171
printstr_base64(const char * text)172 void FAST_FUNC printstr_base64(const char *text)
173 {
174 encode_n_base64(NULL, text, strlen(text));
175 }
176
printbuf_base64(const char * text,unsigned len)177 void FAST_FUNC printbuf_base64(const char *text, unsigned len)
178 {
179 encode_n_base64(NULL, text, len);
180 }
181
printfile_base64(const char * fname)182 void FAST_FUNC printfile_base64(const char *fname)
183 {
184 encode_n_base64(fname, NULL, 0);
185 }
186
187 /*
188 * get username and password from a file descriptor
189 */
get_cred_or_die(int fd)190 void FAST_FUNC get_cred_or_die(int fd)
191 {
192 if (isatty(fd)) {
193 G.user = bb_ask_noecho(fd, /* timeout: */ 0, "User: ");
194 G.pass = bb_ask_noecho(fd, /* timeout: */ 0, "Password: ");
195 } else {
196 G.user = xmalloc_reads(fd, /* maxsize: */ NULL);
197 G.pass = xmalloc_reads(fd, /* maxsize: */ NULL);
198 }
199 if (!G.user || !*G.user || !G.pass)
200 bb_simple_error_msg_and_die("no username or password");
201 }
202