1 files changed, 332 insertions, 0 deletions
diff --git a/smtpd/mail.lmtp.c b/smtpd/mail.lmtp.c
new file mode 100644
index 00000000..90b89990
--- /dev/null
+++ b/smtpd/mail.lmtp.c
@@ -0,0 +1,332 @@
+/*
+ * Copyright (c) 2017 Gilles Chehade <gilles@poolp.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "includes.h"
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <ctype.h>
+#include <err.h>
+#include <errno.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+#include <unistd.h>
+
+enum phase {
+	PHASE_BANNER,
+	PHASE_HELO,
+	PHASE_MAILFROM,
+	PHASE_RCPTTO,
+	PHASE_DATA,
+	PHASE_EOM,
+	PHASE_QUIT
+};
+
+struct session {
+	const char	*lhlo;
+	const char	*mailfrom;
+	char		*rcptto;
+
+	char		**rcpts;
+	int		n_rcpts;
+};
+
+static int lmtp_connect(const char *);
+static void lmtp_engine(int, struct session *);
+static void stream_file(FILE *);
+	
+int
+main(int argc, char *argv[])
+{
+	int ch;
+	int conn;
+	const char *destination = "localhost";
+	struct session	session;
+
+	if (! geteuid())
+		errx(EX_TEMPFAIL, "mail.lmtp: may not be executed as root");
+
+	session.lhlo = "localhost";
+	session.mailfrom = getenv("SENDER");
+	session.rcptto = NULL;
+
+	while ((ch = getopt(argc, argv, "d:l:f:ru")) != -1) {
+		switch (ch) {
+		case 'd':
+			destination = optarg;
+			break;
+		case 'l':
+			session.lhlo = optarg;
+			break;
+		case 'f':
+			session.mailfrom = optarg;
+			break;
+
+		case 'r':
+			session.rcptto = getenv("RECIPIENT");
+			break;
+
+		case 'u':
+			session.rcptto = getenv("USER");
+			break;
+
+		default:
+			break;
+		}
+	}
+	argc -= optind;
+	argv += optind;
+
+	if (session.mailfrom == NULL)
+		errx(EX_TEMPFAIL, "sender must be specified with -f");
+
+	if (argc == 0 && session.rcptto == NULL)
+		errx(EX_TEMPFAIL, "no recipient was specified");
+
+	if (session.rcptto) {
+		session.rcpts = &session.rcptto;
+		session.n_rcpts = 1;
+	}
+	else {
+		session.rcpts = argv;
+		session.n_rcpts = argc;
+	}
+
+	conn = lmtp_connect(destination);
+	lmtp_engine(conn, &session);
+	
+	return (0);
+}
+
+static int
+lmtp_connect_inet(const char *destination)
+{
+	struct addrinfo hints, *res, *res0;
+	char *destcopy = NULL;
+	const char *hostname = NULL;
+	const char *servname = NULL;
+	const char *cause = NULL;
+	char *p;
+	int n, s = -1, save_errno;
+
+	if ((destcopy = strdup(destination)) == NULL)
+		err(EX_TEMPFAIL, NULL);
+
+	servname = "25";
+	hostname = destcopy;
+	p = destcopy;
+	if (*p == '[') {
+		if ((p = strchr(destcopy, ']')) == NULL)
+			errx(EX_TEMPFAIL, "inet: invalid address syntax");
+
+		/* remove [ and ] */
+		*p = '\0';
+		hostname++;
+		if (strncasecmp(hostname, "IPv6:", 5) == 0)
+			hostname += 5;
+
+		/* extract port if any */
+		switch (*(p+1)) {
+		case ':':
+			servname = p+2;
+			break;
+		case '\0':
+			break;
+		default:
+			errx(EX_TEMPFAIL, "inet: invalid address syntax");
+		}
+	}
+	else if ((p = strchr(destcopy, ':')) != NULL) {
+		*p++ = '\0';
+		servname = p;
+	}
+	
+	memset(&hints, 0, sizeof hints);
+	hints.ai_family = PF_UNSPEC;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags = AI_NUMERICSERV;
+	n = getaddrinfo(hostname, servname, &hints, &res0);
+	if (n)
+		errx(EX_TEMPFAIL, "inet: %s", gai_strerror(n));
+
+	for (res = res0; res; res = res->ai_next) {
+		s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
+		if (s == -1) {
+			cause = "socket";
+			continue;
+		}
+
+		if (connect(s, res->ai_addr, res->ai_addrlen) == -1) {
+			cause = "connect";
+			save_errno = errno;
+			close(s);
+			errno = save_errno;
+			s = -1;
+			continue;
+		}
+		break;
+	}
+
+	freeaddrinfo(res0);
+	if (s == -1)
+		errx(EX_TEMPFAIL, "%s", cause);
+
+	free(destcopy);
+	return s;
+}
+
+static int
+lmtp_connect_unix(const char *destination)
+{
+	struct sockaddr_un addr;
+	int s;
+
+	if (*destination != '/')
+		errx(EX_TEMPFAIL, "unix: path must be absolute");
+	
+	if ((s = socket(PF_LOCAL, SOCK_STREAM, 0)) == -1)
+		err(EX_TEMPFAIL, NULL);
+
+	memset(&addr, 0, sizeof addr);
+	addr.sun_family = AF_UNIX;
+	if (strlcpy(addr.sun_path, destination, sizeof addr.sun_path)
+	    >= sizeof addr.sun_path)
+		errx(EX_TEMPFAIL, "unix: socket path is too long");
+
+	if (connect(s, (struct sockaddr *)&addr, sizeof addr) == -1)
+		err(EX_TEMPFAIL, "connect");
+
+	return s;
+}
+
+static int
+lmtp_connect(const char *destination)
+{
+	if (destination[0] == '/')
+		return lmtp_connect_unix(destination);
+	return lmtp_connect_inet(destination);
+}
+
+static void
+lmtp_engine(int fd_read, struct session *session)
+{
+	int fd_write = 0;
+	FILE *file_read = 0;
+	FILE *file_write = 0;
+	char *line = NULL;
+	size_t linesize = 0;
+	ssize_t linelen;
+	enum phase phase = PHASE_BANNER;
+
+	if ((fd_write = dup(fd_read)) == -1)
+		err(EX_TEMPFAIL, "dup");
+
+	if ((file_read = fdopen(fd_read, "r")) == NULL)
+		err(EX_TEMPFAIL, "fdopen");
+
+	if ((file_write = fdopen(fd_write, "w")) == NULL)
+		err(EX_TEMPFAIL, "fdopen");
+
+	do {
+		fflush(file_write);
+
+		if ((linelen = getline(&line, &linesize, file_read)) == -1) {
+			if (ferror(file_read))
+				err(EX_TEMPFAIL, "getline");
+			else
+				errx(EX_TEMPFAIL, "unexpected EOF from LMTP server");
+		}
+		line[strcspn(line, "\n")] = '\0';
+		line[strcspn(line, "\r")] = '\0';
+
+		if (linelen < 4 ||
+		    !isdigit((unsigned char)line[0]) ||
+		    !isdigit((unsigned char)line[1]) ||
+		    !isdigit((unsigned char)line[2]) ||
+		    (line[3] != ' ' && line[3] != '-'))
+			errx(EX_TEMPFAIL, "LMTP server sent an invalid line");
+
+		if (line[0] != (phase == PHASE_DATA ? '3' : '2'))
+			errx(EX_TEMPFAIL, "LMTP server error: %s", line);
+		
+		if (line[3] == '-')
+			continue;
+
+		switch (phase) {
+
+		case PHASE_BANNER:
+			fprintf(file_write, "LHLO %s\r\n", session->lhlo);
+			phase++;
+			break;
+
+		case PHASE_HELO:
+			fprintf(file_write, "MAIL FROM:<%s>\r\n", session->mailfrom);
+			phase++;
+			break;
+
+		case PHASE_MAILFROM:
+			fprintf(file_write, "RCPT TO:<%s>\r\n", session->rcpts[session->n_rcpts - 1]);
+			if (session->n_rcpts - 1 == 0) {
+				phase++;
+				break;
+			}
+			session->n_rcpts--;
+			break;
+
+		case PHASE_RCPTTO:
+			fprintf(file_write, "DATA\r\n");
+			phase++;
+			break;
+
+		case PHASE_DATA:
+			stream_file(file_write);
+			fprintf(file_write, ".\r\n");
+			phase++;
+			break;
+
+		case PHASE_EOM:
+			fprintf(file_write, "QUIT\r\n");
+			phase++;
+			break;						
+
+		case PHASE_QUIT:
+			exit(0);
+		}
+	} while (1);
+}
+
+static void
+stream_file(FILE *conn)
+{
+	char *line = NULL;
+	size_t linesize = 0;
+	ssize_t linelen;
+
+	while ((linelen = getline(&line, &linesize, stdin)) != -1) {
+		line[strcspn(line, "\n")] = '\0';
+		if (line[0] == '.')
+			fprintf(conn, ".");
+		fprintf(conn, "%s\r\n", line);
+	}
+	free(line);
+	if (ferror(stdin))
+		err(EX_TEMPFAIL, "getline");
+}