diff options
Diffstat (limited to 'networking/sendmail.c')
| -rw-r--r-- | networking/sendmail.c | 356 |
1 files changed, 207 insertions, 149 deletions
diff --git a/networking/sendmail.c b/networking/sendmail.c index b2fbc5a..adc6c76 100644 --- a/networking/sendmail.c +++ b/networking/sendmail.c @@ -27,9 +27,13 @@ static void uuencode(char *fname, const char *text) if (NOT_LONE_DASH(fname)) fd = xopen(fname, O_RDONLY); src_buf = bb_common_bufsiz1; - } else { + // 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; fflush(stdout); // sync stdio and unistd output while (1) { @@ -59,7 +63,38 @@ static void uuencode(char *fname, const char *text) close(fd); } -static pid_t helper_pid; +static const char *const init_xargs[9] = { + "openssl", "s_client", "-quiet", "-connect", + NULL, "-tls1", "-starttls", "smtp" +}; + +struct globals { + pid_t helper_pid; + unsigned timeout; + // arguments for SSL connection helper + const char *xargs[9]; +#if ENABLE_FEATURE_FETCHMAIL_FILTER + // arguments for postprocess helper + const char *fargs[3]; +#endif +}; +#define G (*ptr_to_globals) +#define helper_pid (G.helper_pid) +#define timeout (G.timeout ) +#define xargs (G.xargs ) +#define fargs (G.fargs ) +#define INIT_G() do { \ + PTR_TO_GLOBALS = xzalloc(sizeof(G)); \ + memcpy(xargs, init_xargs, sizeof(init_xargs)); \ + fargs[0] = "utf-8"; \ +} while (0) + +#define opt_connect (xargs[4]) +#define opt_after_connect (xargs[5]) +#if ENABLE_FEATURE_FETCHMAIL_FILTER +#define opt_charset (fargs[0]) +#define opt_subject (fargs[1]) +#endif static void kill_helper(void) { @@ -71,7 +106,7 @@ static void kill_helper(void) // generic signal handler static void signal_handler(int signo) { - int err; +#define err signo if (SIGALRM == signo) { kill_helper(); @@ -107,20 +142,19 @@ static void launch_helper(const char **argv) close(pipes[i]); if (!helper_pid) { // child - try to execute connection helper - BB_EXECVP(argv[0], (char **)argv); +// close(STDERR_FILENO); + BB_EXECVP(*argv, (char **)argv); _exit(127); } // parent - check whether child is alive - bb_signals_recursive(0 - + (1 << SIGCHLD) - + (1 << SIGALRM) - , signal_handler); + bb_signals(0 + + (1 << SIGCHLD) + + (1 << SIGALRM) + , signal_handler); signal_handler(SIGCHLD); // child seems OK -> parent goes on } -static unsigned timeout; - static char *command(const char *fmt, const char *param) { char *msg = (char *)fmt; @@ -145,7 +179,9 @@ static int smtp_checkp(const char *fmt, const char *param, int code) // if code != -1 then checks whether the number equals the code // if not equal -> die saying msg #if ENABLE_FEATURE_SENDMAIL_EHLO - while ((answer = xmalloc_getline(stdin)) && '-' == answer[3]) ; + while ((answer = xmalloc_getline(stdin)) != NULL) + if (strlen(answer) <= 3 || '-' != answer[3]) + break; #else answer = xmalloc_getline(stdin); #endif @@ -169,15 +205,31 @@ static 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; +} + +#if ENABLE_FETCHMAIL static void pop3_checkr(const char *fmt, const char *param, char **ret) { char *msg = command(fmt, param); char *answer = xmalloc_getline(stdin); - if (answer && '+' == answer[0]) { + if (answer && '+' == *answer) { alarm(0); if (ret) - *ret = answer; - else + *ret = answer+4; // skip "+OK " + else if (ENABLE_FEATURE_CLEAN_UP) free(answer); return; } @@ -190,28 +242,16 @@ static void pop3_check(const char *fmt, const char *param) pop3_checkr(fmt, param, NULL); } -// 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; -} - -static void pop3_message(int fd) +static void pop3_message(const char *filename) { + int fd; char *answer; - // read stdin, copy to file fd + // create and open file filename + // read stdin, copy to created file + fd = xopen(filename, O_CREAT | O_WRONLY | O_TRUNC | O_EXCL); while ((answer = xmalloc_fgets_str(stdin, "\r\n"))) { char *s = answer; - if ('.' == answer[0]) { + if ('.' == *answer) { if ('.' == answer[1]) s++; else if ('\r' == answer[1] && '\n' == answer[2] && '\0' == answer[3]) @@ -222,64 +262,56 @@ static void pop3_message(int fd) } close(fd); } - -static const char *args[] = { - "openssl", "s_client", "-quiet", "-connect", NULL, "-tls1", "-starttls", "smtp", NULL -}; -#define opt_connect args[4] -#define opt_after_connect args[5] +#endif int sendgetmail_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int sendgetmail_main(int argc, char **argv) { - llist_t *recipients = NULL; - char *from; - const char *subject; - char *charset = (char *)"utf-8"; + llist_t *opt_recipients = NULL; +#if !ENABLE_FEATURE_FETCHMAIL_FILTER + char *opt_subject; + char *opt_charset = (char *)"utf-8"; +#endif const char *opt_user; const char *opt_pass; - const char *opt_timeout; - const char *opt_chdir; enum { - OPT_C = 1 << 0, // chdir - OPT_w = 1 << 1, // network timeout - OPT_U = 1 << 2, // user - OPT_P = 1 << 3, // password - OPT_X = 1 << 4, // use openssl connection helper + OPT_w = 1 << 0, // network timeout + OPT_U = 1 << 1, // user + OPT_P = 1 << 2, // password + OPT_X = 1 << 3, // connect using openssl s_client helper - OPTS_t = 1 << 5, // sendmail "to" - OPTF_t = 1 << 5, // fetchmail "TOP" + OPTS_n = 1 << 4, // sendmail: request notification + OPTF_t = 1 << 4, // fetchmail: use "TOP" not "RETR" - OPTS_f = 1 << 6, // sendmail "from" - OPTF_z = 1 << 6, // fetchmail "delete" + OPTS_s = 1 << 5, // sendmail: subject + OPTF_z = 1 << 5, // fetchmail: delete from server - OPTS_n = 1 << 7, // notification - OPTS_s = 1 << 8, // subject given - OPTS_c = 1 << 9, // charset for subject and body + OPTS_c = 1 << 6, // sendmail: assumed charset + OPTS_t = 1 << 7, // sendmail: recipient(s) }; const char *options; unsigned opts; - // SENDMAIL - if ('s' == applet_name[0]) { - // save initial stdin + INIT_G(); + + if (!ENABLE_FETCHMAIL || 's' == applet_name[0]) { + // SENDMAIL + // save initial stdin (body or attachements can be piped!) xdup2(STDIN_FILENO, INITIAL_STDIN_FILENO); - // -f must be specified - // -t may be multiple - opt_complementary = "-1:f:t::"; - options = "C:w:U:P:X" "t:f:ns:c:"; - // FETCHMAIL + opt_complementary = "-2:w+:t:t::"; // count(-t) > 0 + options = "w:U:P:X" "ns:c:t:"; } else { + // FETCHMAIL opt_after_connect = NULL; - opt_complementary = "=1:P"; - options = "C:w:U:P:X" "tz"; + opt_complementary = "-2:w+:P"; + options = "w:U:P:X" "tz"; } opts = getopt32(argv, options, - &opt_chdir, &opt_timeout, &opt_user, &opt_pass, - &recipients, &from, &subject, &charset + &timeout, &opt_user, &opt_pass, + &opt_subject, &opt_charset, &opt_recipients ); //argc -= optind; @@ -288,16 +320,9 @@ int sendgetmail_main(int argc, char **argv) // first argument is remote server[:port] opt_connect = *argv++; - if (opts & OPT_w) - timeout = xatou(opt_timeout); - - // chdir - if (opts & OPT_C) - xchdir(opt_chdir); - // connect to server if (opts & OPT_X) { - launch_helper(args); + launch_helper(xargs); } else { // no connection helper provided -> make plain connect int fd = create_and_connect_stream_or_die(opt_connect, 0); @@ -305,24 +330,30 @@ int sendgetmail_main(int argc, char **argv) xdup2(STDIN_FILENO, STDOUT_FILENO); } - // randomize - srand(time(NULL)); - - // SENDMAIL - if (recipients) { +#if ENABLE_FETCHMAIL + if (opt_after_connect) +#endif + { + // SENDMAIL + char *opt_from; int code; char *boundary; + const char *fmt; + const char *p; + char *q; // wait for initial OK on plain connect if (!(opts & OPT_X)) smtp_check(NULL, 220); - sane(from); + // get specified sender + opt_from = sane(*argv++); + // introduce to server // should we respect modern (but useless here) EHLO? // or should they respect we wanna be tiny?! - if (!ENABLE_FEATURE_SENDMAIL_EHLO || 250 != smtp_checkp("EHLO %s", from, -1)) { - smtp_checkp("HELO %s", from, 250); + if (!ENABLE_FEATURE_SENDMAIL_EHLO || 250 != smtp_checkp("EHLO %s", opt_from, -1)) { + smtp_checkp("HELO %s", opt_from, 250); } // set sender @@ -330,13 +361,13 @@ int sendgetmail_main(int argc, char **argv) // no authentication is possible code = (opts & OPT_P) ? -1 : 250; // first try softly without authentication - while (250 != smtp_checkp("MAIL FROM:<%s>", from, code)) { + while (250 != smtp_checkp("MAIL FROM:<%s>", opt_from, code)) { // MAIL FROM failed -> authentication needed // do we have username? if (!(opts & OPT_U)) { // no! fetch it from "from" option //opts |= OPT_U; - opt_user = xstrdup(from); + opt_user = xstrdup(opt_from); *strchrnul(opt_user, '@') = '\0'; } // now it seems we have username @@ -351,30 +382,35 @@ int sendgetmail_main(int argc, char **argv) // but now die on failure code = 250; } + // set recipients - for (llist_t *to = recipients; to; to = to->link) { + for (llist_t *to = opt_recipients; to; to = to->link) { smtp_checkp("RCPT TO:<%s>", sane(to->data), 250); } // now put message smtp_check("DATA", 354); // put address headers - printf("From: %s\r\n", from); - for (llist_t *to = recipients; to; to = to->link) { + printf("From: %s\r\n", opt_from); + for (llist_t *to = opt_recipients; to; to = to->link) { printf("To: %s\r\n", to->data); } // put encoded subject if (opts & OPTS_c) - sane(charset); + sane((char *)opt_charset); if (opts & OPTS_s) { - printf("Subject: =?%s?B?", charset); - uuencode(NULL, subject); + printf("Subject: =?%s?B?", opt_charset); + uuencode(NULL, opt_subject); printf("?=\r\n"); } // put notification if (opts & OPTS_n) - printf("Disposition-Notification-To: %s\r\n", from); + printf("Disposition-Notification-To: %s\r\n", opt_from); // put common headers and body start + // randomize +#if ENABLE_FEATURE_SENDMAIL_BLOATY + srand(time(NULL)); +#endif boundary = xasprintf("%d-%d-%d", rand(), rand(), rand()); printf( USE_FEATURE_SENDMAIL_BLOATY("X-Mailer: busybox " BB_VER " sendmail\r\n") @@ -386,16 +422,16 @@ int sendgetmail_main(int argc, char **argv) , boundary ); // put body + attachment(s) - { - const char *fmt = + + fmt = "\r\n--%s\r\n" "%stext/plain; charset=%s\r\n" "%s%s\r\n" "%s" ; - const char *p = charset; - char *q = (char *)""; - while (argv[0]) { + p = opt_charset; + q = (char *)""; + while (*argv) { printf( fmt , boundary @@ -414,9 +450,9 @@ int sendgetmail_main(int argc, char **argv) ; uuencode(*argv, NULL); if (*(++argv)) - q = bb_get_last_path_component_strip(argv[0]); + q = bb_get_last_path_component_strip(*argv); } - } + // put terminator printf("\r\n--%s--\r\n" "\r\n", boundary); if (ENABLE_FEATURE_CLEAN_UP) @@ -426,11 +462,25 @@ int sendgetmail_main(int argc, char **argv) smtp_check(".", 250); smtp_check("QUIT", 221); - // FETCHMAIL +#if ENABLE_FETCHMAIL } else { - // authenticate + // FETCHMAIL char *buf; unsigned nmsg; + char *hostname; + pid_t pid; + // cache fetch command + const char *retr = (opts & OPTF_t) ? "TOP %u 0" : "RETR %u"; + + // goto maildir + xchdir(*argv++); + +#if ENABLE_FEATURE_FETCHMAIL_FILTER + // cache postprocess program + *fargs = *argv; +#endif + + // authenticate if (!(opts & OPT_U)) { //opts |= OPT_U; opt_user = getenv("USER"); @@ -438,25 +488,29 @@ int sendgetmail_main(int argc, char **argv) #if ENABLE_FEATURE_FETCHMAIL_APOP pop3_checkr(NULL, NULL, &buf); // server supports APOP? - if ('<' == buf[4]) { + if ('<' == *buf) { md5_ctx_t md5; - uint8_t hex[16*2 + 1]; // yes. compose <stamp><password> char *s = strchr(buf, '>'); if (s) strcpy(s+1, opt_pass); - s = buf+4; + s = buf; // get md5 sum of <stamp><password> md5_begin(&md5); md5_hash(s, strlen(s), &md5); md5_end(s, &md5); - bin2hex(hex, s, 16); + // NOTE: md5 struct contains enough space + // so we reuse md5 space instead of xzalloc(16*2+1) +#define md5_hex ((uint8_t *)&md5) +// uint8_t *md5_hex = (uint8_t *)&md5; + *bin2hex(md5_hex, s, 16) = '\0'; // APOP - s = xasprintf("%s %s", opt_user, hex); + s = xasprintf("%s %s", opt_user, md5_hex); +#undef md5_hex pop3_check("APOP %s", s); if (ENABLE_FEATURE_CLEAN_UP) { free(s); - free(buf); + free(buf-4); // buf is "+OK " away from malloc'ed string } } else { #else @@ -472,60 +526,64 @@ int sendgetmail_main(int argc, char **argv) // get statistics pop3_checkr("STAT", NULL, &buf); + // prepare message filename suffix + hostname = xzalloc(MAXHOSTNAMELEN+1); + gethostname(hostname, MAXHOSTNAMELEN); + pid = getpid(); + // get number of messages - nmsg = atoi(buf+4); + // NOTE: we don't use xatou(buf) since buf is "nmsg nbytes" + // we only need nmsg and atoi is just exactly what we need + // if atoi fails to convert buf into number it returns 0 + // in this case the following loop simply will not be executed + nmsg = atoi(buf); if (ENABLE_FEATURE_CLEAN_UP) - free(buf); - - // lock maildir - ////USE_FEATURE_CLEAN_UP(close)(xopen(".lock", O_CREAT | O_WRONLY | O_TRUNC | O_EXCL)); - - // make tempnam(dir, salt) respect dir argument - unsetenv("TMPDIR"); - - // TODO: piping through external filter argv... if *argv + free(buf-4); // buf is "+OK " away from malloc'ed string - // cache fetch command - { - const char *retr = (opts & OPTF_t) ? "TOP %u 0" : "RETR %u"; // loop through messages for (; nmsg; nmsg--) { - int fd; - char tmp_name[sizeof("tmp/XXXXXX")]; - char new_name[sizeof("new/XXXXXX")]; - + char *filename = xasprintf("tmp/%llu.%u.%s", monotonic_us(), pid, hostname); + char *target; +#if ENABLE_FEATURE_FETCHMAIL_FILTER + int rc; +#endif // retrieve message in ./tmp - strcpy(tmp_name, "tmp/XXXXXX"); - fd = mkstemp(tmp_name); - if (fd < 0) - bb_perror_msg_and_die("cannot create unique file"); pop3_check(retr, (const char *)nmsg); - pop3_message(fd); // NB: closes fd - - // move file to ./new atomically - strncpy(new_name, "new", 3); - strcpy(new_name + 3, tmp_name + 3); - if (rename(tmp_name, new_name) < 0) { - // rats! such file exists! try to make unique name - strcpy(new_name + 3, "tmp/XXXXXX" + 3); - fd = mkstemp(new_name); - if (fd < 0) - bb_perror_msg_and_die("cannot create unique file"); - close(fd); - xrename(tmp_name, new_name); - } - + pop3_message(filename); // delete message from server if (opts & OPTF_z) pop3_check("DELE %u", (const char*)nmsg); + +#if ENABLE_FEATURE_FETCHMAIL_FILTER + // run postprocessing program + if (*fargs) { + fargs[1] = filename; + rc = wait4pid(spawn((char **)fargs)); + if (99 == rc) + break; + if (1 == rc) + goto skip; + } +#endif + // atomically move message to ./new + target = xstrdup(filename); + strncpy(target, "new", 3); + // ... or just stop receiving on error + if (rename_or_warn(filename, target)) + break; + free(target); +#if ENABLE_FEATURE_FETCHMAIL_FILTER + skip: +#endif + free(filename); } - } + + if (ENABLE_FEATURE_CLEAN_UP) + free(hostname); // Bye pop3_check("QUIT", NULL); - - // unlock maildir - ////unlink(".lock"); +#endif // ENABLE_FETCHMAIL } return 0; |