mailutils/popmaildir.c - busybox - Git at Google

 /* vi: set sw=4 ts=4: */
 /*
  * popmaildir: a simple yet powerful POP3 client
  * Delivers contents of remote mailboxes to local Maildir
  *
  * Inspired by original utility by Nikola Vladov
  *
  * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
  *
  * Licensed under GPLv2, see file LICENSE in this source tree.
  */
 //config:config POPMAILDIR
 //config:	bool "popmaildir (10 kb)"
 //config:	default y
 //config:	help
 //config:	Simple yet powerful POP3 mail popper. Delivers content
 //config:	of remote mailboxes to local Maildir.
 //config:
 //config:config FEATURE_POPMAILDIR_DELIVERY
 //config:	bool "Allow message filters and custom delivery program"
 //config:	default y
 //config:	depends on POPMAILDIR
 //config:	help
 //config:	Allow to use a custom program to filter the content
 //config:	of the message before actual delivery (-F "prog [args...]").
 //config:	Allow to use a custom program for message actual delivery
 //config:	(-M "prog [args...]").

 //applet:IF_POPMAILDIR(APPLET(popmaildir, BB_DIR_USR_SBIN, BB_SUID_DROP))

 //kbuild:lib-$(CONFIG_POPMAILDIR) += popmaildir.o mail.o

 //usage:#define popmaildir_trivial_usage
 //usage:       "[OPTIONS] MAILDIR [CONN_HELPER ARGS]"
 //usage:#define popmaildir_full_usage "\n\n"
 //usage:       "Fetch content of remote mailbox to local maildir\n"
 /* //usage:  "\n	-b		Binary mode. Ignored" */
 /* //usage:  "\n	-d		Debug. Ignored" */
 /* //usage:  "\n	-m		Show used memory. Ignored" */
 /* //usage:  "\n	-V		Show version. Ignored" */
 /* //usage:  "\n	-c		Use tcpclient. Ignored" */
 /* //usage:  "\n	-a		Use APOP protocol. Implied. If server supports APOP -> use it" */
 //usage:     "\n	-s		Skip authorization"
 //usage:     "\n	-T		Get messages with TOP instead of RETR"
 //usage:     "\n	-k		Keep retrieved messages on the server"
 //usage:     "\n	-t SEC		Network timeout"
 //usage:	IF_FEATURE_POPMAILDIR_DELIVERY(
 //usage:     "\n	-F 'PROG ARGS'	Filter program (may be repeated)"
 //usage:     "\n	-M 'PROG ARGS'	Delivery program"
 //usage:	)
 //usage:     "\n"
 //usage:     "\nFetch from plain POP3 server:"
 //usage:     "\npopmaildir -k DIR nc pop3.server.com 110 <user_and_pass.txt"
 //usage:     "\nFetch from SSLed POP3 server and delete fetched emails:"
 //usage:     "\npopmaildir DIR -- openssl s_client -quiet -connect pop3.server.com:995 <user_and_pass.txt"
 /* //usage:  "\n	-R BYTES	Remove old messages on the server >= BYTES. Ignored" */
 /* //usage:  "\n	-Z N1-N2	Remove messages from N1 to N2 (dangerous). Ignored" */
 /* //usage:  "\n	-L BYTES	Don't retrieve new messages >= BYTES. Ignored" */
 /* //usage:  "\n	-H LINES	Type first LINES of a message. Ignored" */
 //usage:
 //usage:#define popmaildir_example_usage
 //usage:       "$ popmaildir -k ~/Maildir -- nc pop.drvv.ru 110 [<password_file]\n"
 //usage:       "$ popmaildir ~/Maildir -- openssl s_client -quiet -connect pop.gmail.com:995 [<password_file]\n"

 #include "libbb.h"
 #include "mail.h"

 static void pop3_checkr(const char *fmt, const char *param, char **ret)
 {
 	char *msg = send_mail_command(fmt, param);
 	char *answer = xmalloc_fgetline(stdin);
 	if (answer && '+' == answer[0]) {
 		free(msg);
 		if (timeout)
 			alarm(0);
 		if (ret) {
 			// skip "+OK "
 			memmove(answer, answer + 4, strlen(answer) - 4);
 			*ret = answer;
 		} else
 			free(answer);
 		return;
 	}
 	bb_error_msg_and_die("%s failed, reply was: %s", msg, answer);
 }

 static void pop3_check(const char *fmt, const char *param)
 {
 	pop3_checkr(fmt, param, NULL);
 }

 int popmaildir_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int popmaildir_main(int argc UNUSED_PARAM, char **argv)
 {
 	char *buf;
 	unsigned nmsg;
 	char *hostname;
 	pid_t pid;
 	const char *retr;
 #if ENABLE_FEATURE_POPMAILDIR_DELIVERY
 	const char *delivery;
 #endif
 	unsigned opt_nlines = 0;

 	enum {
 		OPT_b = 1 << 0,		// -b binary mode. Ignored
 		OPT_d = 1 << 1,		// -d,-dd,-ddd debug. Ignored
 		OPT_m = 1 << 2,		// -m show used memory. Ignored
 		OPT_V = 1 << 3,		// -V version. Ignored
 		OPT_c = 1 << 4,		// -c use tcpclient. Ignored
 		OPT_a = 1 << 5,		// -a use APOP protocol
 		OPT_s = 1 << 6,		// -s skip authorization
 		OPT_T = 1 << 7,		// -T get messages with TOP instead with RETR
 		OPT_k = 1 << 8,		// -k keep retrieved messages on the server
 		OPT_t = 1 << 9,		// -t90 set timeout to 90 sec
 		OPT_R = 1 << 10,	// -R20000 remove old messages on the server >= 20000 bytes (requires -k). Ignored
 		OPT_Z = 1 << 11,	// -Z11-23 remove messages from 11 to 23 (dangerous). Ignored
 		OPT_L = 1 << 12,	// -L50000 not retrieve new messages >= 50000 bytes. Ignored
 		OPT_H = 1 << 13,	// -H30 type first 30 lines of a message; (-L12000 -H30). Ignored
 		OPT_M = 1 << 14,	// -M\"program arg1 arg2 ...\"; deliver by program. Treated like -F
 		OPT_F = 1 << 15,	// -F\"program arg1 arg2 ...\"; filter by program. Treated like -M
 	};

 	// init global variables
 	INIT_G();

 	// parse options
 	opts = getopt32(argv, "^"
 		"bdmVcasTkt:+" "R:+Z:L:+H:+" IF_FEATURE_POPMAILDIR_DELIVERY("M:F:")
 		"\0" "-1:dd",
 		&timeout, NULL, NULL, NULL, &opt_nlines
 		IF_FEATURE_POPMAILDIR_DELIVERY(, &delivery, &delivery) // we treat -M and -F the same
 	);
 	//argc -= optind;
 	argv += optind;

 	// get auth info
 	if (!(opts & OPT_s))
 		get_cred_or_die(STDIN_FILENO);

 	// goto maildir
 	xchdir(*argv++);

 	// launch connect helper, if any
 	if (*argv)
 		launch_helper((const char **)argv);

 	// get server greeting
 	pop3_checkr(NULL, NULL, &buf);

 	// authenticate (if no -s given)
 	if (!(opts & OPT_s)) {
 		// server supports APOP and we want it?
 		if ('<' == buf[0] && (opts & OPT_a)) {
 			union { // save a bit of stack
 				md5_ctx_t ctx;
 				char hex[16 * 2 + 1];
 			} md5;
 			uint32_t res[16 / 4];

 			char *s = strchr(buf, '>');
 			if (s)
 				s[1] = '\0';
 			// get md5 sum of "<stamp>password" string
 			md5_begin(&md5.ctx);
 			md5_hash(&md5.ctx, buf, strlen(buf));
 			md5_hash(&md5.ctx, G.pass, strlen(G.pass));
 			md5_end(&md5.ctx, res);
 			*bin2hex(md5.hex, (char*)res, 16) = '\0';
 			// APOP
 			s = xasprintf("%s %s", G.user, md5.hex);
 			pop3_check("APOP %s", s);
 			free(s);
 			free(buf);
 		// server ignores APOP -> use simple text authentication
 		} else {
 			// USER
 			pop3_check("USER %s", G.user);
 			// PASS
 			pop3_check("PASS %s", G.pass);
 		}
 	}

 	// get mailbox statistics
 	pop3_checkr("STAT", NULL, &buf);

 	// prepare message filename suffix
 	hostname = safe_gethostname();
 	pid = getpid();

 	// get messages counter
 	// 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);
 	free(buf);

 	// loop through messages
 	retr = (opts & OPT_T) ? xasprintf("TOP %%u %u", opt_nlines) : "RETR %u";
 	for (; nmsg; nmsg--) {

 		char *filename;
 		char *target;
 		char *answer;
 		FILE *fp;
 #if ENABLE_FEATURE_POPMAILDIR_DELIVERY
 		int rc;
 #endif
 		// generate unique filename
 		filename  = xasprintf("tmp/%llu.%u.%s",
 			monotonic_us(), (unsigned)pid, hostname);

 		// retrieve message in ./tmp/ unless filter is specified
 		pop3_check(retr, (const char *)(ptrdiff_t)nmsg);

 #if ENABLE_FEATURE_POPMAILDIR_DELIVERY
 		// delivery helper ordered? -> setup pipe
 		if (opts & (OPT_F|OPT_M)) {
 			// helper will have $FILENAME set to filename
 			xsetenv("FILENAME", filename);
 			fp = popen(delivery, "w");
 			unsetenv("FILENAME");
 			if (!fp) {
 				bb_simple_perror_msg("delivery helper");
 				break;
 			}
 		} else
 #endif
 		// create and open file filename
 		fp = xfopen_for_write(filename);

 		// copy stdin to fp (either filename or delivery helper)
 		while ((answer = xmalloc_fgets_str(stdin, "\r\n")) != NULL) {
 			char *s = answer;
 			if ('.' == answer[0]) {
 				if ('.' == answer[1])
 					s++;
 				else if ('\r' == answer[1] && '\n' == answer[2] && '\0' == answer[3])
 					break;
 			}
 			//*strchrnul(s, '\r') = '\n';
 			fputs(s, fp);
 			free(answer);
 		}

 #if ENABLE_FEATURE_POPMAILDIR_DELIVERY
 		// analyse delivery status
 		if (opts & (OPT_F|OPT_M)) {
 			rc = pclose(fp);
 			if (99 == rc) // 99 means bail out
 				break;
 //			if (rc) // !0 means skip to the next message
 				goto skip;
 //			// 0 means continue
 		} else {
 			// close filename
 			fclose(fp);
 		}
 #endif

 		// delete message from server
 		if (!(opts & OPT_k))
 			pop3_check("DELE %u", (const char*)(ptrdiff_t)nmsg);

 		// atomically move message to ./new/
 		target = xstrdup(filename);
 		memcpy(target, "new", 3);
 		// ... or just stop receiving on failure
 		if (rename_or_warn(filename, target))
 			break;
 		free(target);

 #if ENABLE_FEATURE_POPMAILDIR_DELIVERY
  skip:
 #endif
 		free(filename);
 	}

 	// Bye
 	pop3_check("QUIT", NULL);

 	if (ENABLE_FEATURE_CLEAN_UP) {
 		free(G.user);
 		free(G.pass);
 	}

 	return EXIT_SUCCESS;
 }
	/* vi: set sw=4 ts=4: */
	/*
	* popmaildir: a simple yet powerful POP3 client
	* Delivers contents of remote mailboxes to local Maildir
	*
	* Inspired by original utility by Nikola Vladov
	*
	* Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
	*
	* Licensed under GPLv2, see file LICENSE in this source tree.
	*/
	//config:config POPMAILDIR
	//config: bool "popmaildir (10 kb)"
	//config: default y
	//config: help
	//config: Simple yet powerful POP3 mail popper. Delivers content
	//config: of remote mailboxes to local Maildir.
	//config:
	//config:config FEATURE_POPMAILDIR_DELIVERY
	//config: bool "Allow message filters and custom delivery program"
	//config: default y
	//config: depends on POPMAILDIR
	//config: help
	//config: Allow to use a custom program to filter the content
	//config: of the message before actual delivery (-F "prog [args...]").
	//config: Allow to use a custom program for message actual delivery
	//config: (-M "prog [args...]").

	//applet:IF_POPMAILDIR(APPLET(popmaildir, BB_DIR_USR_SBIN, BB_SUID_DROP))

	//kbuild:lib-$(CONFIG_POPMAILDIR) += popmaildir.o mail.o

	//usage:#define popmaildir_trivial_usage
	//usage: "[OPTIONS] MAILDIR [CONN_HELPER ARGS]"
	//usage:#define popmaildir_full_usage "\n\n"
	//usage: "Fetch content of remote mailbox to local maildir\n"
	/* //usage: "\n -b Binary mode. Ignored" */
	/* //usage: "\n -d Debug. Ignored" */
	/* //usage: "\n -m Show used memory. Ignored" */
	/* //usage: "\n -V Show version. Ignored" */
	/* //usage: "\n -c Use tcpclient. Ignored" */
	/* //usage: "\n -a Use APOP protocol. Implied. If server supports APOP -> use it" */
	//usage: "\n -s Skip authorization"
	//usage: "\n -T Get messages with TOP instead of RETR"
	//usage: "\n -k Keep retrieved messages on the server"
	//usage: "\n -t SEC Network timeout"
	//usage: IF_FEATURE_POPMAILDIR_DELIVERY(
	//usage: "\n -F 'PROG ARGS' Filter program (may be repeated)"
	//usage: "\n -M 'PROG ARGS' Delivery program"
	//usage: )
	//usage: "\n"
	//usage: "\nFetch from plain POP3 server:"
	//usage: "\npopmaildir -k DIR nc pop3.server.com 110 <user_and_pass.txt"
	//usage: "\nFetch from SSLed POP3 server and delete fetched emails:"
	//usage: "\npopmaildir DIR -- openssl s_client -quiet -connect pop3.server.com:995 <user_and_pass.txt"
	/* //usage: "\n -R BYTES Remove old messages on the server >= BYTES. Ignored" */
	/* //usage: "\n -Z N1-N2 Remove messages from N1 to N2 (dangerous). Ignored" */
	/* //usage: "\n -L BYTES Don't retrieve new messages >= BYTES. Ignored" */
	/* //usage: "\n -H LINES Type first LINES of a message. Ignored" */
	//usage:
	//usage:#define popmaildir_example_usage
	//usage: "$ popmaildir -k ~/Maildir -- nc pop.drvv.ru 110 [<password_file]\n"
	//usage: "$ popmaildir ~/Maildir -- openssl s_client -quiet -connect pop.gmail.com:995 [<password_file]\n"

	#include "libbb.h"
	#include "mail.h"

	static void pop3_checkr(const char fmt, const char param, char **ret)
	{
	char *msg = send_mail_command(fmt, param);
	char *answer = xmalloc_fgetline(stdin);
	if (answer && '+' == answer[0]) {
	free(msg);
	if (timeout)
	alarm(0);
	if (ret) {
	// skip "+OK "
	memmove(answer, answer + 4, strlen(answer) - 4);
	*ret = answer;
	} else
	free(answer);
	return;
	}
	bb_error_msg_and_die("%s failed, reply was: %s", msg, answer);
	}

	static void pop3_check(const char fmt, const char param)
	{
	pop3_checkr(fmt, param, NULL);
	}

	int popmaildir_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
	int popmaildir_main(int argc UNUSED_PARAM, char **argv)
	{
	char *buf;
	unsigned nmsg;
	char *hostname;
	pid_t pid;
	const char *retr;
	#if ENABLE_FEATURE_POPMAILDIR_DELIVERY
	const char *delivery;
	#endif
	unsigned opt_nlines = 0;

	enum {
	OPT_b = 1 << 0, // -b binary mode. Ignored
	OPT_d = 1 << 1, // -d,-dd,-ddd debug. Ignored
	OPT_m = 1 << 2, // -m show used memory. Ignored
	OPT_V = 1 << 3, // -V version. Ignored
	OPT_c = 1 << 4, // -c use tcpclient. Ignored
	OPT_a = 1 << 5, // -a use APOP protocol
	OPT_s = 1 << 6, // -s skip authorization
	OPT_T = 1 << 7, // -T get messages with TOP instead with RETR
	OPT_k = 1 << 8, // -k keep retrieved messages on the server
	OPT_t = 1 << 9, // -t90 set timeout to 90 sec
	OPT_R = 1 << 10, // -R20000 remove old messages on the server >= 20000 bytes (requires -k). Ignored
	OPT_Z = 1 << 11, // -Z11-23 remove messages from 11 to 23 (dangerous). Ignored
	OPT_L = 1 << 12, // -L50000 not retrieve new messages >= 50000 bytes. Ignored
	OPT_H = 1 << 13, // -H30 type first 30 lines of a message; (-L12000 -H30). Ignored
	OPT_M = 1 << 14, // -M\"program arg1 arg2 ...\"; deliver by program. Treated like -F
	OPT_F = 1 << 15, // -F\"program arg1 arg2 ...\"; filter by program. Treated like -M
	};

	// init global variables
	INIT_G();

	// parse options
	opts = getopt32(argv, "^"
	"bdmVcasTkt:+" "R:+Z:L:+H:+" IF_FEATURE_POPMAILDIR_DELIVERY("M:F:")
	"\0" "-1:dd",
	&timeout, NULL, NULL, NULL, &opt_nlines
	IF_FEATURE_POPMAILDIR_DELIVERY(, &delivery, &delivery) // we treat -M and -F the same
	);
	//argc -= optind;
	argv += optind;

	// get auth info
	if (!(opts & OPT_s))
	get_cred_or_die(STDIN_FILENO);

	// goto maildir
	xchdir(*argv++);

	// launch connect helper, if any
	if (*argv)
	launch_helper((const char **)argv);

	// get server greeting
	pop3_checkr(NULL, NULL, &buf);

	// authenticate (if no -s given)
	if (!(opts & OPT_s)) {
	// server supports APOP and we want it?
	if ('<' == buf[0] && (opts & OPT_a)) {
	union { // save a bit of stack
	md5_ctx_t ctx;
	char hex[16 * 2 + 1];
	} md5;
	uint32_t res[16 / 4];

	char *s = strchr(buf, '>');
	if (s)
	s[1] = '\0';
	// get md5 sum of "<stamp>password" string
	md5_begin(&md5.ctx);
	md5_hash(&md5.ctx, buf, strlen(buf));
	md5_hash(&md5.ctx, G.pass, strlen(G.pass));
	md5_end(&md5.ctx, res);
	bin2hex(md5.hex, (char)res, 16) = '\0';
	// APOP
	s = xasprintf("%s %s", G.user, md5.hex);
	pop3_check("APOP %s", s);
	free(s);
	free(buf);
	// server ignores APOP -> use simple text authentication
	} else {
	// USER
	pop3_check("USER %s", G.user);
	// PASS
	pop3_check("PASS %s", G.pass);
	}
	}

	// get mailbox statistics
	pop3_checkr("STAT", NULL, &buf);

	// prepare message filename suffix
	hostname = safe_gethostname();
	pid = getpid();

	// get messages counter
	// 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);
	free(buf);

	// loop through messages
	retr = (opts & OPT_T) ? xasprintf("TOP %%u %u", opt_nlines) : "RETR %u";
	for (; nmsg; nmsg--) {

	char *filename;
	char *target;
	char *answer;
	FILE *fp;
	#if ENABLE_FEATURE_POPMAILDIR_DELIVERY
	int rc;
	#endif
	// generate unique filename
	filename = xasprintf("tmp/%llu.%u.%s",
	monotonic_us(), (unsigned)pid, hostname);

	// retrieve message in ./tmp/ unless filter is specified
	pop3_check(retr, (const char *)(ptrdiff_t)nmsg);

	#if ENABLE_FEATURE_POPMAILDIR_DELIVERY
	// delivery helper ordered? -> setup pipe
	if (opts & (OPT_F\|OPT_M)) {
	// helper will have $FILENAME set to filename
	xsetenv("FILENAME", filename);
	fp = popen(delivery, "w");
	unsetenv("FILENAME");
	if (!fp) {
	bb_simple_perror_msg("delivery helper");
	break;
	}
	} else
	#endif
	// create and open file filename
	fp = xfopen_for_write(filename);

	// copy stdin to fp (either filename or delivery helper)
	while ((answer = xmalloc_fgets_str(stdin, "\r\n")) != NULL) {
	char *s = answer;
	if ('.' == answer[0]) {
	if ('.' == answer[1])
	s++;
	else if ('\r' == answer[1] && '\n' == answer[2] && '\0' == answer[3])
	break;
	}
	//*strchrnul(s, '\r') = '\n';
	fputs(s, fp);
	free(answer);
	}

	#if ENABLE_FEATURE_POPMAILDIR_DELIVERY
	// analyse delivery status
	if (opts & (OPT_F\|OPT_M)) {
	rc = pclose(fp);
	if (99 == rc) // 99 means bail out
	break;
	// if (rc) // !0 means skip to the next message
	goto skip;
	// // 0 means continue
	} else {
	// close filename
	fclose(fp);
	}
	#endif

	// delete message from server
	if (!(opts & OPT_k))
	pop3_check("DELE %u", (const char*)(ptrdiff_t)nmsg);

	// atomically move message to ./new/
	target = xstrdup(filename);
	memcpy(target, "new", 3);
	// ... or just stop receiving on failure
	if (rename_or_warn(filename, target))
	break;
	free(target);

	#if ENABLE_FEATURE_POPMAILDIR_DELIVERY
	skip:
	#endif
	free(filename);
	}

	// Bye
	pop3_check("QUIT", NULL);

	if (ENABLE_FEATURE_CLEAN_UP) {
	free(G.user);
	free(G.pass);
	}

	return EXIT_SUCCESS;
	}