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authorDenis Vlasenko2008-11-06 23:41:38 +0000
committerDenis Vlasenko2008-11-06 23:41:38 +0000
commitb9d572a2733fa20957a9a3287bd04d66176e3b6a (patch)
tree2b9ff7454709e84b02e644db4914ad9d4b739e68 /networking/sendmail.c
parentf10bc3964f1d92fa83ec97a625fca33ce1592f26 (diff)
downloadbusybox-b9d572a2733fa20957a9a3287bd04d66176e3b6a.zip
busybox-b9d572a2733fa20957a9a3287bd04d66176e3b6a.tar.gz
total overhaul of mail applets. again. Vladimir as usual.
Diffstat (limited to 'networking/sendmail.c')
-rw-r--r--networking/sendmail.c563
1 files changed, 0 insertions, 563 deletions
diff --git a/networking/sendmail.c b/networking/sendmail.c
deleted file mode 100644
index 9602b89..0000000
--- a/networking/sendmail.c
+++ /dev/null
@@ -1,563 +0,0 @@
-/* vi: set sw=4 ts=4: */
-/*
- * bare bones sendmail
- *
- * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
- *
- * Licensed under GPLv2, see file LICENSE in this tarball for details.
- */
-#include "libbb.h"
-
-struct globals {
- pid_t helper_pid;
- unsigned timeout;
- FILE *fp0; // initial stdin
- // arguments for SSL connection helper
- const char *xargs[9];
-};
-#define G (*ptr_to_globals)
-#define helper_pid (G.helper_pid)
-#define timeout (G.timeout )
-#define fp0 (G.fp0 )
-#define xargs (G.xargs )
-#define INIT_G() do { \
- SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
- xargs[0] = "openssl"; \
- xargs[1] = "s_client"; \
- xargs[2] = "-quiet"; \
- xargs[3] = "-connect"; \
- /*xargs[4] = "localhost";*/ \
- xargs[5] = "-tls1"; \
- xargs[6] = "-starttls"; \
- xargs[7] = "smtp"; \
-} while (0)
-
-#define opt_connect (xargs[4])
-
-static void uuencode(char *fname, const char *text)
-{
- enum {
- SRC_BUF_SIZE = 45, /* This *MUST* be a multiple of 3 */
- DST_BUF_SIZE = 4 * ((SRC_BUF_SIZE + 2) / 3),
- };
-
-#define src_buf text
- FILE *fp = fp;
- ssize_t len = len;
- char dst_buf[DST_BUF_SIZE + 1];
-
- if (fname) {
- fp = (NOT_LONE_DASH(fname)) ? xfopen_for_read(fname) : fp0;
- src_buf = bb_common_bufsiz1;
- // N.B. strlen(NULL) segfaults!
- } else if (text) {
- // though we do not call uuencode(NULL, NULL) explicitly
- // still we do not want to break things suddenly
- len = strlen(text);
- } else
- return;
-
- while (1) {
- size_t size;
- if (fname) {
- size = fread((char *)src_buf, 1, SRC_BUF_SIZE, fp);
- if ((ssize_t)size < 0)
- bb_perror_msg_and_die(bb_msg_read_error);
- } else {
- size = len;
- if (len > SRC_BUF_SIZE)
- size = SRC_BUF_SIZE;
- }
- if (!size)
- break;
- // encode the buffer we just read in
- bb_uuencode(dst_buf, src_buf, size, bb_uuenc_tbl_base64);
- if (fname) {
- printf("\r\n");
- } else {
- src_buf += size;
- len -= size;
- }
- fwrite(dst_buf, 1, 4 * ((size + 2) / 3), stdout);
- }
- if (fname)
- fclose(fp);
-#undef src_buf
-}
-
-
-#if ENABLE_FEATURE_SENDMAIL_SSL
-static void kill_helper(void)
-{
- // TODO!!!: is there more elegant way to terminate child on program failure?
- if (helper_pid > 0)
- kill(helper_pid, SIGTERM);
-}
-
-// generic signal handler
-static void signal_handler(int signo)
-{
-#define err signo
- if (SIGALRM == signo) {
- kill_helper();
- bb_error_msg_and_die("timed out");
- }
-
- // SIGCHLD. reap zombies
- if (wait_any_nohang(&err) > 0)
- if (WIFEXITED(err)) {
-// if (WEXITSTATUS(err))
- bb_error_msg_and_die("child exited (%d)", WEXITSTATUS(err));
-// else
-// kill(0, SIGCONT);
- }
-#undef err
-}
-
-static void launch_helper(const char **argv)
-{
- // setup vanilla unidirectional pipes interchange
- int idx;
- int pipes[4];
-
- xpipe(pipes);
- xpipe(pipes+2);
- helper_pid = vfork();
- if (helper_pid < 0)
- bb_perror_msg_and_die("vfork");
- idx = (!helper_pid) * 2;
- xdup2(pipes[idx], STDIN_FILENO);
- xdup2(pipes[3-idx], STDOUT_FILENO);
- if (ENABLE_FEATURE_CLEAN_UP)
- for (int i = 4; --i >= 0; )
- if (pipes[i] > STDOUT_FILENO)
- close(pipes[i]);
- if (!helper_pid) {
- // child: try to execute connection helper
- BB_EXECVP(*argv, (char **)argv);
- _exit(127);
- }
- // parent: check whether child is alive
- bb_signals(0
- + (1 << SIGCHLD)
- + (1 << SIGALRM)
- , signal_handler);
- signal_handler(SIGCHLD);
- // child seems OK -> parent goes on
-}
-#else
-#define kill_helper() ((void)0)
-#define launch_helper(x) bb_error_msg_and_die("no SSL support")
-#endif
-
-static const char *command(const char *fmt, const char *param)
-{
- const char *msg = fmt;
- alarm(timeout);
- if (msg) {
- msg = xasprintf(fmt, param);
- printf("%s\r\n", msg);
- }
- fflush(stdout);
- return msg;
-}
-
-static int smtp_checkp(const char *fmt, const char *param, int code)
-{
- char *answer;
- const char *msg = command(fmt, param);
- // read stdin
- // if the string has a form \d\d\d- -- read next string. E.g. EHLO response
- // parse first bytes to a number
- // if code = -1 then just return this number
- // if code != -1 then checks whether the number equals the code
- // if not equal -> die saying msg
- while ((answer = xmalloc_fgetline(stdin)) != NULL)
- if (strlen(answer) <= 3 || '-' != answer[3])
- break;
- if (answer) {
- int n = atoi(answer);
- alarm(0);
- free(answer);
- if (-1 == code || n == code)
- return n;
- }
- kill_helper();
- bb_error_msg_and_die("%s failed", msg);
-}
-
-static inline int smtp_check(const char *fmt, int code)
-{
- return smtp_checkp(fmt, NULL, code);
-}
-
-// strip argument of bad chars
-static char *sane(char *str)
-{
- char *s = str;
- char *p = s;
- while (*s) {
- if (isalnum(*s) || '_' == *s || '-' == *s || '.' == *s || '@' == *s) {
- *p++ = *s;
- }
- s++;
- }
- *p = '\0';
- return str;
-}
-
-// NB: parse_url can modify url[] (despite const), but only if '@' is there
-static const char *parse_url(const char *url, const char **user, const char **pass)
-{
- // parse [user[:pass]@]host
- // return host
- char *s = strchr(url, '@');
- *user = *pass = NULL;
- if (s) {
- *s++ = '\0';
- *user = url;
- url = s;
- s = strchr(*user, ':');
- if (s) {
- *s++ = '\0';
- *pass = s;
- }
- }
- return url;
-}
-
-static void rcptto(const char *s)
-{
- smtp_checkp("RCPT TO:<%s>", s, 250);
-}
-
-int sendmail_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int sendmail_main(int argc UNUSED_PARAM, char **argv)
-{
-#if ENABLE_FEATURE_SENDMAIL_MAILX
- llist_t *opt_attachments = NULL;
- const char *opt_subject;
- const char *opt_charset = CONFIG_FEATURE_SENDMAIL_CHARSET;
-#if ENABLE_FEATURE_SENDMAIL_MAILXX
- llist_t *opt_carboncopies = NULL;
- char *opt_errors_to;
-#endif
-#endif
- char *opt_from, *opt_fullname;
- const char *opt_user;
- const char *opt_pass;
- int code;
- char *boundary;
- llist_t *l;
- llist_t *headers = NULL;
- char *domain = sane(safe_getdomainname());
- unsigned opts;
-
- enum {
- OPT_w = 1 << 0, // network timeout
- OPT_H = 1 << 1, // [user:password@]server[:port]
- OPT_S = 1 << 2, // connect using openssl s_client helper
- OPT_t = 1 << 3, // read message for recipients
- OPT_N = 1 << 4, // request notification
- OPT_f = 1 << 5, // sender address
- OPT_F = 1 << 6, // sender name, overrides $NAME
-#if ENABLE_FEATURE_SENDMAIL_MAILX
- OPT_s = 1 << 7, // subject
- OPT_j = 1 << 8, // assumed charset
- OPT_a = 1 << 9, // attachment(s)
-#if ENABLE_FEATURE_SENDMAIL_MAILXX
- OPT_c = 1 << 10, // carbon copy
- OPT_e = 1 << 11, // errors-to address
-#endif
-#endif
- };
-
- // init global variables
- INIT_G();
-
- // save initial stdin since body is piped!
- xdup2(STDIN_FILENO, 3);
- fp0 = fdopen(3, "r");
-
- // parse options
- opt_complementary = "w+:a::" USE_FEATURE_SENDMAIL_MAILXX("c::");
- opts = getopt32(argv,
- "w:H:St" "N:f:F:" USE_FEATURE_SENDMAIL_MAILX("s:j:a:") USE_FEATURE_SENDMAIL_MAILXX("c:e:")
- "X:V:vq:R:O:o:nmL:Iih:GC:B:b:A:" // postfix compat only, ignored
- // r:Q:p:M:Dd are candidates from another man page. TODO?
- "46E", // ssmtp introduces another quirks. TODO?: -a[upm] (user, pass, method) to be supported
- &timeout /* -w */, &opt_connect /* -H */,
- NULL, &opt_from, &opt_fullname,
- USE_FEATURE_SENDMAIL_MAILX(&opt_subject, &opt_charset, &opt_attachments,)
- USE_FEATURE_SENDMAIL_MAILXX(&opt_carboncopies, &opt_errors_to,)
- NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
- );
- //argc -= optind;
- argv += optind;
-
- // connect to server
- // host[:port] not specified ? -> use $SMTPHOST. no $SMTPHOST ? -> use localhost
- if (!(opts & OPT_H)) {
- opt_connect = getenv("SMTPHOST");
- if (!opt_connect)
- opt_connect = "127.0.0.1";
- }
- // fetch username and password, if any
- // NB: parse_url modifies opt_connect[] ONLY if '@' is there.
- // Thus "127.0.0.1" won't be modified, an is ok that it is RO.
- opt_connect = parse_url(opt_connect, &opt_user, &opt_pass);
-
- // username must be defined!
- if (!opt_user) {
- // N.B. IMHO getenv("USER") can be way easily spoofed!
- opt_user = bb_getpwuid(NULL, -1, getuid());
- }
-
- // SSL ordered? ->
- if (opts & OPT_S) {
- // ... use openssl helper
- launch_helper(xargs);
- // no SSL ordered? ->
- } else {
- // ... make plain connect
- int fd = create_and_connect_stream_or_die(opt_connect, 25);
- // make ourselves a simple IO filter
- // from now we know nothing about network :)
- xmove_fd(fd, STDIN_FILENO);
- xdup2(STDIN_FILENO, STDOUT_FILENO);
- }
-
- // got no sender address? -> use username as a resort
- if (!(opts & OPT_f)) {
- opt_from = xasprintf("%s@%s", opt_user, domain);
- }
-
- // introduce to server
-
- // we didn't use SSL helper? ->
- if (!(opts & OPT_S)) {
- // ... wait for initial server OK
- smtp_check(NULL, 220);
- }
-
- // we should start with modern EHLO
- if (250 != smtp_checkp("EHLO %s", domain, -1)) {
- smtp_checkp("HELO %s", domain, 250);
- }
- if (ENABLE_FEATURE_CLEAN_UP)
- free(domain);
-
- // set sender
- // NOTE: if password has not been specified
- // then no authentication is possible
- code = (opt_pass ? -1 : 250);
- // first try softly without authentication
- while (250 != smtp_checkp("MAIL FROM:<%s>", opt_from, code)) {
- // MAIL FROM failed -> authentication needed
- if (334 == smtp_check("AUTH LOGIN", -1)) {
- uuencode(NULL, opt_user); // opt_user != NULL
- smtp_check("", 334);
- uuencode(NULL, opt_pass);
- smtp_check("", 235);
- }
- // authenticated OK? -> retry to set sender
- // but this time die on failure!
- code = 250;
- }
-
- // recipients specified as arguments
- while (*argv) {
- char *s = sane(*argv);
- // loose test on email address validity
- if (strchr(s, '@')) {
- rcptto(s);
- llist_add_to_end(&headers, xasprintf("To: %s", s));
- }
- argv++;
- }
-
-#if ENABLE_FEATURE_SENDMAIL_MAILXX
- // carbon copies recipients specified as -c options
- for (l = opt_carboncopies; l; l = l->link) {
- char *s = sane(l->data);
- // loose test on email address validity
- if (strchr(s, '@')) {
- rcptto(s);
- // TODO: do we ever need to mangle the message?
- //llist_add_to_end(&headers, xasprintf("Cc: %s", s));
- }
- }
-#endif
-
- // if -t specified or no recipients specified -> read recipients from message
- // i.e. scan stdin for To:, Cc:, Bcc: lines ...
- // ... and then use the rest of stdin as message body
- // N.B. subject read from body can be further overrided with one specified on command line.
- // recipients are merged. Bcc: lines are deleted
- // N.B. other headers are collected and will be dumped verbatim
- if (opts & OPT_t || !headers) {
- // fetch recipients and (optionally) subject
- char *s;
- while ((s = xmalloc_fgetline(fp0)) != NULL) {
- if (0 == strncasecmp("To: ", s, 4) || 0 == strncasecmp("Cc: ", s, 4)) {
- rcptto(sane(s+4));
- llist_add_to_end(&headers, s);
- } else if (0 == strncasecmp("Bcc: ", s, 5)) {
- rcptto(sane(s+5));
- free(s);
- // N.B. Bcc vanishes from headers!
- } else if (0 == strncmp("Subject: ", s, 9)) {
- // we read subject -> use it verbatim unless it is specified
- // on command line
-#if ENABLE_FEATURE_SENDMAIL_MAILX
- if (opts & OPT_s)
- free(s);
- else
-#endif
- llist_add_to_end(&headers, s);
- } else if (s[0]) {
- // misc header
- llist_add_to_end(&headers, s);
- } else {
- free(s);
- break; // stop on the first empty line
- }
- }
- }
-
- // enter "put message" mode
- smtp_check("DATA", 354);
-
- // put headers we could have preread with -t
- for (l = headers; l; l = l->link) {
- printf("%s\r\n", l->data);
- if (ENABLE_FEATURE_CLEAN_UP)
- free(l->data);
- }
-
- // put (possibly encoded) subject
-#if ENABLE_FEATURE_SENDMAIL_MAILX
- if (opts & OPT_j)
- sane((char *)opt_charset);
- if (opts & OPT_s) {
- printf("Subject: ");
- if (opts & OPT_j) {
- printf("=?%s?B?", opt_charset);
- uuencode(NULL, opt_subject);
- printf("?=");
- } else {
- printf("%s", opt_subject);
- }
- printf("\r\n");
- }
-#endif
-
- // put sender name, $NAME is the default
- if (!(opts & OPT_F))
- opt_fullname = getenv("NAME");
- if (opt_fullname)
- printf("From: \"%s\" <%s>\r\n", opt_fullname, opt_from);
-
- // put notification
- if (opts & OPT_N)
- printf("Disposition-Notification-To: %s\r\n", opt_from);
-
-#if ENABLE_FEATURE_SENDMAIL_MAILXX
- // put errors recipient
- if (opts & OPT_e)
- printf("Errors-To: %s\r\n", opt_errors_to);
-#endif
-
- // make a random string -- it will delimit message parts
- srand(monotonic_us());
- boundary = xasprintf("%d-%d-%d", rand(), rand(), rand());
-
- // put common headers
- // TODO: do we really need this?
-// printf("Message-ID: <%s>\r\n", boundary);
-
-#if ENABLE_FEATURE_SENDMAIL_MAILX
- // have attachments? -> compose multipart MIME
- if (opt_attachments) {
- const char *fmt;
- const char *p;
- char *q;
-
- printf(
- "Mime-Version: 1.0\r\n"
- "%smultipart/mixed; boundary=\"%s\"\r\n"
- , "Content-Type: "
- , boundary
- );
-
- // body is pseudo attachment read from stdin in first turn
- llist_add_to(&opt_attachments, (char *)"-");
-
- // put body + attachment(s)
- // N.B. all these weird things just to be tiny
- // by reusing string patterns!
- fmt =
- "\r\n--%s\r\n"
- "%stext/plain; charset=%s\r\n"
- "%s%s\r\n"
- "%s"
- ;
- p = opt_charset;
- q = (char *)"";
- l = opt_attachments;
- while (l) {
- printf(
- fmt
- , boundary
- , "Content-Type: "
- , p
- , "Content-Disposition: inline"
- , q
- , "Content-Transfer-Encoding: base64\r\n"
- );
- p = "";
- fmt =
- "\r\n--%s\r\n"
- "%sapplication/octet-stream%s\r\n"
- "%s; filename=\"%s\"\r\n"
- "%s"
- ;
- uuencode(l->data, NULL);
- l = l->link;
- if (l)
- q = bb_get_last_path_component_strip(l->data);
- }
-
- // put message terminator
- printf("\r\n--%s--\r\n" "\r\n", boundary);
-
- // no attachments? -> just dump message
- } else
-#endif
- {
- char *s;
- // terminate headers
- printf("\r\n");
- // put plain text respecting leading dots
- while ((s = xmalloc_fgetline(fp0)) != NULL) {
- // escape leading dots
- // N.B. this feature is implied even if no -i (-oi) switch given
- // N.B. we need to escape the leading dot regardless of
- // whether it is single or not character on the line
- if ('.' == s[0] /*&& '\0' == s[1] */)
- printf(".");
- // dump read line
- printf("%s\r\n", s);
- }
- }
-
- // leave "put message" mode
- smtp_check(".", 250);
- // ... and say goodbye
- smtp_check("QUIT", 221);
- // cleanup
- if (ENABLE_FEATURE_CLEAN_UP)
- fclose(fp0);
-
- return EXIT_SUCCESS;
-}