diff options
Diffstat (limited to 'networking')
| -rw-r--r-- | networking/Config.in | 35 | ||||
| -rw-r--r-- | networking/Kbuild | 1 | ||||
| -rw-r--r-- | networking/sendmail.c | 630 |
3 files changed, 445 insertions, 221 deletions
diff --git a/networking/Config.in b/networking/Config.in index e8820e1..ed87a17 100644 --- a/networking/Config.in +++ b/networking/Config.in @@ -671,12 +671,39 @@ config SENDMAIL help Barebones sendmail. -config FEATURE_SENDMAIL_NETWORK - bool "Support network connectivity" - default y +config FEATURE_SENDMAIL_EHLO + bool "Support EHLO command" + default n + depends on SENDMAIL + help + Support ESMTP EHLO command. + +config FEATURE_SENDMAIL_BLOATY + bool "Be more verbose" + default n depends on SENDMAIL help - Add ability to send, not only compose messages. + Should be turned off. + +config FETCHMAIL + bool "fetchmail" + default n + help + Barebones fetchmail. + +config FEATURE_FETCHMAIL_APOP + bool "Support APOP authentication" + default y + depends on FETCHMAIL + help + Support secure APOP authentication. + +config FEATURE_FETCHMAIL_FILTER + bool "Pipe thru external filter" + default n + depends on FETCHMAIL + help + Support piping incoming messages thru external filter. config SLATTACH bool "slattach" diff --git a/networking/Kbuild b/networking/Kbuild index 2819e85..8f309cd 100644 --- a/networking/Kbuild +++ b/networking/Kbuild @@ -11,6 +11,7 @@ lib-$(CONFIG_BRCTL) += brctl.o lib-$(CONFIG_DNSD) += dnsd.o lib-$(CONFIG_ETHER_WAKE) += ether-wake.o lib-$(CONFIG_FAKEIDENTD) += isrv_identd.o isrv.o +lib-$(CONFIG_FETCHMAIL) += sendmail.o lib-$(CONFIG_FTPGET) += ftpgetput.o lib-$(CONFIG_FTPPUT) += ftpgetput.o lib-$(CONFIG_HOSTNAME) += hostname.o diff --git a/networking/sendmail.c b/networking/sendmail.c index fa1abc7..5dababc 100644 --- a/networking/sendmail.c +++ b/networking/sendmail.c @@ -1,6 +1,6 @@ /* vi: set sw=4 ts=4: */ /* - * bare bones sendmail + * bare bones sendmail/fetchmail * * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com> * @@ -8,23 +8,24 @@ */ #include "libbb.h" -/* - Extracted from BB uuencode.c - */ -enum { - SRC_BUF_SIZE = 45, /* This *MUST* be a multiple of 3 */ - DST_BUF_SIZE = 4 * ((SRC_BUF_SIZE + 2) / 3), -}; +#define INITIAL_STDIN_FILENO 3 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 int fd; #define len fd char dst_buf[DST_BUF_SIZE + 1]; if (fname) { - fd = xopen(fname, O_RDONLY); + fd = INITIAL_STDIN_FILENO; + if (NOT_LONE_DASH(fname)) + fd = xopen(fname, O_RDONLY); src_buf = bb_common_bufsiz1; } else { len = strlen(text); @@ -44,69 +45,147 @@ static void uuencode(char *fname, const char *text) } if (!size) break; - // Encode the buffer we just read in + // encode the buffer we just read in bb_uuencode(dst_buf, src_buf, size, bb_uuenc_tbl_base64); if (fname) { - xwrite(STDOUT_FILENO, "\n", 1); + xwrite(STDOUT_FILENO, "\r\n", 2); } else { src_buf += size; len -= size; } xwrite(STDOUT_FILENO, dst_buf, 4 * ((size + 2) / 3)); } - if (ENABLE_FEATURE_CLEAN_UP && fname) + if (fname) close(fd); } -#if ENABLE_FEATURE_SENDMAIL_NETWORK +static pid_t helper_pid; + +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) { int err; - if (SIGALRM == 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) && WEXITSTATUS(err)) +#if ENABLE_FEATURE_SENDMAIL_BLOATY bb_error_msg_and_die("child exited (%d)", WEXITSTATUS(err)); +#else + bb_error_msg_and_die("child failed"); +#endif } -static pid_t helper_pid; - -// read stdin, parses first bytes to a number, i.e. server response -// if code = -1 then just return this number -// if code != -1 then checks whether the number equals the code -// if not equal -> die saying errmsg -static int check(int code, const char *errmsg) +static void launch_helper(const char **argv) { - char *answer; + // 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[0], (char **)argv); + _exit(127); + } + // parent - check whether child is alive + sig_catch(SIGCHLD, signal_handler); + sig_catch(SIGALRM, signal_handler); + signal_handler(SIGCHLD); + // child seems OK -> parent goes on +} + +static unsigned timeout; - // read a string and match it against the set of available answers +static char *command(const char *fmt, const char *param) +{ + char *msg = (char *)fmt; + alarm(timeout); + if (msg) { +// if (param) + 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; + 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 +#if ENABLE_FEATURE_SENDMAIL_EHLO + while ((answer = xmalloc_getline(stdin)) && '-' == answer[3]) ; +#else answer = xmalloc_getline(stdin); +#endif if (answer) { int n = atoi(answer); - if (-1 == code || n == code) { + alarm(0); + if (ENABLE_FEATURE_CLEAN_UP) { + free(msg); free(answer); + } + if (-1 == code || n == code) { return n; } } - // TODO: is there more elegant way to terminate child on program failure? - if (helper_pid > 0) - kill(helper_pid, SIGTERM); - if (!answer) - answer = (char*)"EOF"; - else - *strchrnul(answer, '\r') = '\0'; - bb_error_msg_and_die("error at %s: got '%s' instead", errmsg, answer); + kill_helper(); + bb_error_msg_and_die("%s failed", msg); } -static int puts_and_check(const char *msg, int code, const char *errmsg) +static int smtp_check(const char *fmt, int code) { - printf("%s\r\n", msg); - return check(code, errmsg); + return smtp_checkp(fmt, NULL, code); +} + +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]) { + alarm(0); + if (ret) + *ret = answer; + else + free(answer); + return; + } + kill_helper(); + bb_error_msg_and_die("%s failed", msg); +} + +static void pop3_check(const char *fmt, const char *param) +{ + pop3_checkr(fmt, param, NULL); } // strip argument of bad chars @@ -123,215 +202,332 @@ static char *sane(char *str) *p = '\0'; return str; } -#endif -int sendmail_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; -int sendmail_main(int argc, char **argv) +static void pop3_message(int fd) +{ + char *answer; + // read stdin, copy to file fd + while ((answer = xmalloc_fgets_str(stdin, "\r\n"))) { + char *s = answer; + if ('.' == answer[0]) { + if ('.' == answer[1]) + s++; + else if ('\r' == answer[1] && '\n' == answer[2] && '\0' == answer[3]) + break; + } + xwrite(fd, s, strlen(s)); + free(answer); + } + 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] + +int sendgetmail_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int sendgetmail_main(int argc, char **argv) { llist_t *recipients = NULL; - llist_t *bodies = NULL; - llist_t *attachments = NULL; char *from; - char *notify = NULL; const char *subject; - char *charset = (char*)"utf-8"; -#if ENABLE_FEATURE_SENDMAIL_NETWORK - const char *wsecs = "10"; - const char *server = "127.0.0.1"; - const char *port = NULL; + char *charset = (char *)"utf-8"; + const char *opt_user; const char *opt_pass; - unsigned timeout; -#endif - char *boundary; - unsigned opts; + const char *opt_timeout; + const char *opt_chdir; + enum { - OPT_f = 1 << 0, // sender - OPT_n = 1 << 2, // notification - OPT_s = 1 << 3, // subject given - OPT_c = 1 << 6, // charset - OPT_d = 1 << 7, // dry run - no networking - OPT_w = 1 << 8, // network timeout - OPT_h = 1 << 9, // server - OPT_p = 1 << 10, // port - OPT_U = 1 << 11, // user specified - OPT_P = 1 << 12, // password specified + 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 + + OPTS_t = 1 << 5, // sendmail "to" + OPTF_t = 1 << 5, // fetchmail "TOP" + + OPTS_f = 1 << 6, // sendmail "from" + OPTF_z = 1 << 6, // fetchmail "delete" + + OPTS_n = 1 << 7, // notification + OPTS_s = 1 << 8, // subject given + OPTS_c = 1 << 9, // charset for subject and body }; - // -f must be specified - // -t, -b, -a may be multiple - opt_complementary = "f:t::b::a::"; - opts = getopt32(argv, - "f:t:n::s:b:a:c:" USE_FEATURE_SENDMAIL_NETWORK("dw:h:p:U:P:"), - &from, &recipients, ¬ify, &subject, &bodies, &attachments, &charset - USE_FEATURE_SENDMAIL_NETWORK(, &wsecs, &server, &port, &opt_user, &opt_pass) + const char *options; + unsigned opts; + + // SENDMAIL + if ('s' == applet_name[0]) { + // save initial stdin + 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 + } else { + opt_after_connect = NULL; + opt_complementary = "=1:P"; + options = "C:w:U:P:X" "tz"; + } + opts = getopt32(argv, options, + &opt_chdir, &opt_timeout, &opt_user, &opt_pass, + &recipients, &from, &subject, &charset ); + //argc -= optind; argv += optind; - // sanitize user input - sane(from); - if (opts & OPT_c) - sane(charset); - - // establish connection -#if ENABLE_FEATURE_SENDMAIL_NETWORK - timeout = xatou(wsecs); - if (!(opts & OPT_d)) { - // ask password if we need to and while we're still have terminal - // TODO: get password directly from /dev/tty? or from a secret file? - if ((opts & (OPT_U+OPT_P)) == OPT_U) { - if (!isatty(STDIN_FILENO) || !(opt_pass = bb_askpass(0, "Password: "))) { - bb_error_msg_and_die("no password"); - } + // 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); + } else { + // no connection helper provided -> make plain connect + int fd = create_and_connect_stream_or_die(opt_connect, 0); + xmove_fd(fd, STDIN_FILENO); + xdup2(STDIN_FILENO, STDOUT_FILENO); + } + + // randomize + srand(time(NULL)); + + // SENDMAIL + if (recipients) { + int code; + char *boundary; + + // wait for initial OK on plain connect + if (!(opts & OPT_X)) + smtp_check(NULL, 220); + + sane(from); + // 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); } - // set chat timeout - alarm(timeout); - // connect to server - if (argv[0]) { - // if connection helper given - // 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]); - // replace child with connection helper - if (!helper_pid) { - // child - try to execute connection helper - BB_EXECVP(argv[0], argv); - _exit(127); + + // set sender + // NOTE: if password has not been specified -> + // no authentication is possible + code = (opts & OPT_P) ? -1 : 250; + // first try softly without authentication + while (250 != smtp_checkp("MAIL FROM:<%s>", 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); + *strchrnul(opt_user, '@') = '\0'; } - // parent - check whether child is alive - sig_catch(SIGCHLD, signal_handler); - sig_catch(SIGALRM, signal_handler); - signal_handler(SIGCHLD); - // child seems OK -> parent goes on SMTP chat - } else { - // no connection helper provided -> make plain connect - int fd = create_and_connect_stream_or_die( - server, - bb_lookup_port(port, "tcp", 25) - ); - xmove_fd(fd, STDIN_FILENO); - xdup2(STDIN_FILENO, STDOUT_FILENO); - // wait for OK - check(220, "INIT"); + // now it seems we have username + // try to authenticate + if (334 == smtp_check("AUTH LOGIN", -1)) { + uuencode(NULL, opt_user); + smtp_check("", 334); + uuencode(NULL, opt_pass); + smtp_check("", 235); + } + // authenticated -> retry set sender + // but now die on failure + code = 250; } - // mail user specified? try modern AUTHentication - if ((opts & OPT_U) - && (334 == puts_and_check("auth login", -1, "auth login")) - ) { - uuencode(NULL, opt_user); - puts_and_check("", 334, "AUTH"); - uuencode(NULL, opt_pass); - puts_and_check("", 235, "AUTH"); - // no mail user specified or modern AUTHentication is not supported? - } else { - // fallback to simple HELO authentication - // fetch domain name (defaults to local) - const char *domain = strchr(from, '@'); - if (domain) - domain++; - else - domain = "local"; - printf("helo %s\r\n", domain); - check(250, "HELO"); + // set recipients + for (llist_t *to = recipients; to; to = to->link) { + smtp_checkp("RCPT TO:<%s>", sane(to->data), 250); } - // set addresses - printf("mail from:<%s>\r\n", from); - check(250, "MAIL FROM"); + // 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("rcpt to:<%s>\r\n", sane(to->data)); - check(250, "RCPT TO"); + printf("To: %s\r\n", to->data); } - puts_and_check("data", 354, "DATA"); - // no timeout while sending message - alarm(0); - } -#endif - - // now put message - // put address headers - printf("From: %s\r\n", from); - for (llist_t *to = recipients; to; to = to->link) { - printf("To: %s\r\n", sane(to->data)); - } - // put encoded subject - if (opts & OPT_s) { - printf("Subject: =?%s?B?", charset); - uuencode(NULL, subject); - puts("?=\r"); - } - // put notification - if (opts & OPT_n) { - // -n without parameter? - if (!notify) - notify = from; // notify sender by default - printf("Disposition-Notification-To: %s\r\n", sane(notify)); - } - // put common headers and body start - //srand(?); - boundary = xasprintf("%d-%d-%d", rand(), rand(), rand()); - printf( - "X-Mailer: busybox " BB_VER " sendmail\r\n" - "Message-ID: <%s>\r\n" - "Mime-Version: 1.0\r\n" - "%smultipart/mixed; boundary=\"%s\"\r\n" - "\r\n" - "--%s\r\n" - "%stext/plain; charset=%s\r\n" - "%s\r\n%s" - , boundary - , "Content-Type: " - , boundary, boundary - , "Content-Type: " - , charset - , "Content-Disposition: inline" - , "Content-Transfer-Encoding: base64\r\n" - ); - // put body(ies) - for (llist_t *f = bodies; f; f = f->link) { - uuencode(f->data, NULL); - } - // put attachment(s) - for (llist_t *f = attachments; f; f = f->link) { + // put encoded subject + if (opts & OPTS_c) + sane(charset); + if (opts & OPTS_s) { + printf("Subject: =?%s?B?", charset); + uuencode(NULL, subject); + printf("?=\r\n"); + } + // put notification + if (opts & OPTS_n) + printf("Disposition-Notification-To: %s\r\n", from); + // put common headers and body start + boundary = xasprintf("%d-%d-%d", rand(), rand(), rand()); printf( - "\r\n--%s\r\n" - "%sapplication/octet-stream\r\n" - "%s; filename=\"%s\"\r\n" - "%s" + USE_FEATURE_SENDMAIL_BLOATY("X-Mailer: busybox " BB_VER " sendmail\r\n") + "Message-ID: <%s>\r\n" + "Mime-Version: 1.0\r\n" + "%smultipart/mixed; boundary=\"%s\"\r\n" , boundary , "Content-Type: " - , "Content-Disposition: inline" - , bb_get_last_path_component_strip(f->data) - , "Content-Transfer-Encoding: base64\r\n" + , boundary ); - uuencode(f->data, NULL); - } - // put terminator - printf("\r\n--%s--\r\n\r\n", boundary); - if (ENABLE_FEATURE_CLEAN_UP) - free(boundary); - -#if ENABLE_FEATURE_SENDMAIL_NETWORK - // end message and say goodbye - if (!(opts & OPT_d)) { - alarm(timeout); - puts_and_check(".", 250, "BODY"); - puts_and_check("quit", 221, "QUIT"); + // put body + attachment(s) + { + const char *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]) { + 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(*argv, NULL); + if (*(++argv)) + q = bb_get_last_path_component_strip(argv[0]); + } } + // put terminator + printf("\r\n--%s--\r\n" "\r\n", boundary); + if (ENABLE_FEATURE_CLEAN_UP) + free(boundary); + + // end message and say goodbye + smtp_check(".", 250); + smtp_check("QUIT", 221); + + // FETCHMAIL + } else { + // authenticate + char *buf; + unsigned nmsg; + if (!(opts & OPT_U)) { + //opts |= OPT_U; + opt_user = getenv("USER"); + } +#if ENABLE_FEATURE_FETCHMAIL_APOP + pop3_checkr(NULL, NULL, &buf); + // server supports APOP? + if ('<' == buf[4]) { + 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; + // get md5 sum of <stamp><password> + md5_begin(&md5); + md5_hash(s, strlen(s), &md5); + md5_end(s, &md5); + bin2hex(hex, s, 16); + // APOP + s = xasprintf("%s %s", opt_user, hex); + pop3_check("APOP %s", s); + if (ENABLE_FEATURE_CLEAN_UP) { + free(s); + free(buf); + } + } else { +#else + { + pop3_check(NULL, NULL); #endif + // USER + pop3_check("USER %s", opt_user); + // PASS + pop3_check("PASS %s", opt_pass); + } + + // get statistics + pop3_checkr("STAT", NULL, &buf); + + // get number of messages + nmsg = atoi(buf+4); + 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 thru external filter argv... if *argv + + // cache fetch command + { + const char *retr = (opts & OPTF_t) ? "TOP %u 0" : "RETR %u"; + // loop thru messages + for (; nmsg; nmsg--) { + int fd; + char tmp_name[sizeof("tmp/XXXXXX")]; + char new_name[sizeof("new/XXXXXX")]; + + // 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); + if (rename(tmp_name, new_name) < 0) { + // something is very wrong + bb_perror_msg_and_die("cannot move %s to %s", tmp_name, new_name); + } + } + + // delete message from server + if (opts & OPTF_z) + pop3_check("DELE %u", (const char*)nmsg); + } + } + + // Bye + pop3_check("QUIT", NULL); + + // unlock maildir + ////unlink(".lock"); + } return 0; } |