/*
* smtp.c -- nmh SMTP interface
*
- * $Id$
- *
* This code is Copyright (c) 2002, by the authors of nmh. See the
* COPYRIGHT file in the root directory of the nmh distribution for
* complete copyright information.
#ifdef CYRUS_SASL
#include <sasl/sasl.h>
#include <sasl/saslutil.h>
+# if SASL_VERSION_FULL < 0x020125
+ /* Cyrus SASL 2.1.25 introduced the sasl_callback_ft prototype,
+ which has an explicit void parameter list, according to best
+ practice. So we need to cast to avoid compile warnings.
+ Provide this prototype for earlier versions. */
+ typedef int (*sasl_callback_ft)();
+# endif /* SASL_VERSION_FULL < 0x020125 */
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#endif /* CYRUS_SASL */
+#ifdef TLS_SUPPORT
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#endif /* TLS_SUPPORT */
+
/*
* This module implements an interface to SendMail very similar
* to the MMDF mm_(3) routines. The sm_() routines herein talk
#define SM_DOT 600 /* see above */
#define SM_QUIT 30
#define SM_CLOS 10
+#ifdef CYRUS_SASL
#define SM_AUTH 45
+#endif /* CYRUS_SASL */
static int sm_addrs = 0;
static int sm_alarmed = 0;
static int maxoutbuf; /* Maximum crypto output buffer */
static char *sasl_outbuffer; /* SASL output buffer for encryption */
static int sasl_outbuflen; /* Current length of data in outbuf */
-static char *sasl_inbuffer; /* SASL input buffer for encryption */
-static char *sasl_inptr; /* Pointer to current inbuf position */
-static int sasl_inbuflen; /* Current length of data in inbuf */
static int sm_get_user(void *, int, const char **, unsigned *);
static int sm_get_pass(sasl_conn_t *, void *, int, sasl_secret_t **);
-static int sm_fgetc(FILE *);
static sasl_callback_t callbacks[] = {
- { SASL_CB_USER, sm_get_user, NULL },
+ { SASL_CB_USER, (sasl_callback_ft) sm_get_user, NULL },
#define SM_SASL_N_CB_USER 0
- { SASL_CB_PASS, sm_get_pass, NULL },
+ { SASL_CB_PASS, (sasl_callback_ft) sm_get_pass, NULL },
#define SM_SASL_N_CB_PASS 1
- { SASL_CB_AUTHNAME, sm_get_user, NULL },
+ { SASL_CB_AUTHNAME, (sasl_callback_ft) sm_get_user, NULL },
#define SM_SASL_N_CB_AUTHNAME 2
{ SASL_CB_LIST_END, NULL, NULL },
};
-#define SASL_MAXRECVBUF 65536
#else /* CYRUS_SASL */
-#define sm_fgetc fgetc
+int sasl_ssf = 0;
#endif /* CYRUS_SASL */
+#ifdef TLS_SUPPORT
+static SSL_CTX *sslctx = NULL;
+static SSL *ssl = NULL;
+static BIO *sbior = NULL;
+static BIO *sbiow = NULL;
+static BIO *io = NULL;
+#endif /* TLS_SUPPORT */
+
+#if defined(CYRUS_SASL) || defined(TLS_SUPPORT)
+#define SASL_MAXRECVBUF 65536
+static int sm_fgetc(FILE *);
+static char *sasl_inbuffer; /* SASL input buffer for encryption */
+static char *sasl_inptr; /* Pointer to current inbuf position */
+static int sasl_inbuflen; /* Current length of data in inbuf */
+#else
+#define sm_fgetc fgetc
+#endif
+
+static int tls_active = 0;
+
static char *sm_noreply = "No reply text given";
static char *sm_moreply = "; ";
* static prototypes
*/
static int smtp_init (char *, char *, char *, int, int, int, int, int, int,
- char *, char *);
-static int sendmail_init (char *, char *, int, int, int, int, int);
+ char *, char *, int);
+static int sendmail_init (char *, char *, int, int, int, int, int, int,
+ char *, char *);
static int rclient (char *, char *);
static int sm_ierror (char *fmt, ...);
static int smhear (void);
static int sm_rrecord (char *, int *);
static int sm_rerror (int);
-static RETSIGTYPE alrmser (int);
+static void alrmser (int);
static char *EHLOset (char *);
static int sm_fwrite(char *, int);
static int sm_fputs(char *);
* Function prototypes needed for SASL
*/
-static int sm_auth_sasl(char *, char *, char *);
+static int sm_auth_sasl(char *, int, char *, char *);
#endif /* CYRUS_SASL */
int
sm_init (char *client, char *server, char *port, int watch, int verbose,
- int debug, int onex, int queued, int sasl, char *saslmech,
- char *user)
+ int debug, int queued, int sasl, int saslssf,
+ char *saslmech, char *user, int tls)
{
if (sm_mts == MTS_SMTP)
return smtp_init (client, server, port, watch, verbose,
- debug, onex, queued, sasl, saslmech, user);
+ debug, queued, sasl, saslssf, saslmech,
+ user, tls);
else
return sendmail_init (client, server, watch, verbose,
- debug, onex, queued);
+ debug, queued, sasl, saslssf, saslmech,
+ user);
}
static int
smtp_init (char *client, char *server, char *port, int watch, int verbose,
- int debug, int onex, int queued, int sasl, char *saslmech,
- char *user)
+ int debug, int queued,
+ int sasl, int saslssf, char *saslmech, char *user, int tls)
{
+ int result, sd1, sd2;
#ifdef CYRUS_SASL
char *server_mechs;
+#else /* CYRUS_SASL */
+ NMH_UNUSED (sasl);
+ NMH_UNUSED (saslssf);
+ NMH_UNUSED (saslmech);
+ NMH_UNUSED (user);
#endif /* CYRUS_SASL */
- int result, sd1, sd2;
if (watch)
verbose = TRUE;
if (clientname) {
client = clientname;
} else {
- client = LocalName(); /* no clientname -> LocalName */
+ client = LocalName(1); /* no clientname -> LocalName */
}
}
-#ifdef ZMAILER
+ /*
+ * Last-ditch check just in case client still isn't set to anything
+ */
+
if (client == NULL || *client == '\0')
client = "localhost";
-#endif
-#ifdef CYRUS_SASL
+#if defined(CYRUS_SASL) || defined(TLS_SUPPORT)
sasl_inbuffer = malloc(SASL_MAXRECVBUF);
if (!sasl_inbuffer)
return sm_ierror("Unable to allocate %d bytes for read buffer",
SASL_MAXRECVBUF);
-#endif /* CYRUS_SASL */
+#endif /* CYRUS_SASL || TLS_SUPPORT */
if ((sd1 = rclient (server, port)) == NOTOK)
return RP_BHST;
return sm_ierror ("unable to fdopen");
}
+ tls_active = 0;
+
sm_alarmed = 0;
alarm (SM_OPEN);
result = smhear ();
/*
* Give EHLO or HELO command
*/
- if (client && *client) {
+
+ doingEHLO = 1;
+ result = smtalk (SM_HELO, "EHLO %s", client);
+ doingEHLO = 0;
+
+ if (result >= 500 && result <= 599)
+ result = smtalk (SM_HELO, "HELO %s", client);
+
+ if (result != 250) {
+ sm_end (NOTOK);
+ return RP_RPLY;
+ }
+
+#ifdef TLS_SUPPORT
+ /*
+ * If the user requested TLS support, then try to do the STARTTLS command
+ * as part of the initial dialog. Assuming this works, we then need to
+ * restart the EHLO dialog after TLS negotiation is complete.
+ */
+
+ if (tls) {
+ BIO *ssl_bio;
+
+ if (! EHLOset("STARTTLS")) {
+ sm_end(NOTOK);
+ return sm_ierror("SMTP server does not support TLS");
+ }
+
+ result = smtalk(SM_HELO, "STARTTLS");
+
+ if (result != 220) {
+ sm_end(NOTOK);
+ return RP_RPLY;
+ }
+
+ /*
+ * Okay, the other side should be waiting for us to start TLS
+ * negotiation. Oblige them.
+ */
+
+ if (! sslctx) {
+ const SSL_METHOD *method;
+
+ SSL_library_init();
+ SSL_load_error_strings();
+
+ method = TLSv1_client_method(); /* Not sure about this */
+
+ sslctx = SSL_CTX_new(method);
+
+ if (! sslctx) {
+ sm_end(NOTOK);
+ return sm_ierror("Unable to initialize OpenSSL context: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ }
+ }
+
+ ssl = SSL_new(sslctx);
+
+ if (! ssl) {
+ sm_end(NOTOK);
+ return sm_ierror("Unable to create SSL connection: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ }
+
+ sbior = BIO_new_socket(fileno(sm_rfp), BIO_NOCLOSE);
+ sbiow = BIO_new_socket(fileno(sm_wfp), BIO_NOCLOSE);
+
+ if (sbior == NULL || sbiow == NULL) {
+ sm_end(NOTOK);
+ return sm_ierror("Unable to create BIO endpoints: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ }
+
+ SSL_set_bio(ssl, sbior, sbiow);
+ SSL_set_connect_state(ssl);
+
+ /*
+ * Set up a BIO to handle buffering for us
+ */
+
+ io = BIO_new(BIO_f_buffer());
+
+ if (! io) {
+ sm_end(NOTOK);
+ return sm_ierror("Unable to create a buffer BIO: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ }
+
+ ssl_bio = BIO_new(BIO_f_ssl());
+
+ if (! ssl_bio) {
+ sm_end(NOTOK);
+ return sm_ierror("Unable to create a SSL BIO: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ }
+
+ BIO_set_ssl(ssl_bio, ssl, BIO_CLOSE);
+ BIO_push(io, ssl_bio);
+
+ /*
+ * Try doing the handshake now
+ */
+
+ if (BIO_do_handshake(io) < 1) {
+ sm_end(NOTOK);
+ return sm_ierror("Unable to negotiate SSL connection: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ }
+
+ if (sm_debug) {
+ const SSL_CIPHER *cipher = SSL_get_current_cipher(ssl);
+ printf("SSL negotiation successful: %s(%d) %s\n",
+ SSL_CIPHER_get_name(cipher),
+ SSL_CIPHER_get_bits(cipher, NULL),
+ SSL_CIPHER_get_version(cipher));
+
+ }
+
+ tls_active = 1;
+
doingEHLO = 1;
result = smtalk (SM_HELO, "EHLO %s", client);
doingEHLO = 0;
- if (result >= 500 && result <= 599)
- result = smtalk (SM_HELO, "HELO %s", client);
-
if (result != 250) {
sm_end (NOTOK);
return RP_RPLY;
}
}
+#else /* TLS_SUPPORT */
+ NMH_UNUSED (tls);
+#endif /* TLS_SUPPORT */
#ifdef CYRUS_SASL
/*
saslmech, server_mechs);
}
- if (sm_auth_sasl(user, saslmech ? saslmech : server_mechs,
+ if (sm_auth_sasl(user, saslssf, saslmech ? saslmech : server_mechs,
server) != RP_OK) {
sm_end(NOTOK);
return NOTOK;
send_options: ;
if (watch && EHLOset ("XVRB"))
smtalk (SM_HELO, "VERB on");
- if (onex && EHLOset ("XONE"))
- smtalk (SM_HELO, "ONEX");
if (queued && EHLOset ("XQUE"))
smtalk (SM_HELO, "QUED");
int
sendmail_init (char *client, char *server, int watch, int verbose,
- int debug, int onex, int queued)
+ int debug, int queued,
+ int sasl, int saslssf, char *saslmech, char *user)
{
- int i, result, vecp;
+ unsigned int i, result, vecp;
int pdi[2], pdo[2];
char *vec[15];
+#ifdef CYRUS_SASL
+ char *server_mechs;
+#else /* CYRUS_SASL */
+ NMH_UNUSED (server);
+ NMH_UNUSED (sasl);
+ NMH_UNUSED (saslssf);
+ NMH_UNUSED (saslmech);
+ NMH_UNUSED (user);
+#endif /* CYRUS_SASL */
if (watch)
verbose = TRUE;
if (clientname)
client = clientname;
else
- client = LocalName(); /* no clientname -> LocalName */
+ client = LocalName(1); /* no clientname -> LocalName */
}
-#ifdef ZMAILER
+ /*
+ * Last-ditch check just in case client still isn't set to anything
+ */
+
if (client == NULL || *client == '\0')
client = "localhost";
-#endif
-#ifdef CYRUS_SASL
+#if defined(CYRUS_SASL) || defined(TLS_SUPPORT)
sasl_inbuffer = malloc(SASL_MAXRECVBUF);
if (!sasl_inbuffer)
return sm_ierror("Unable to allocate %d bytes for read buffer",
SASL_MAXRECVBUF);
-#endif /* CYRUS_SASL */
+#endif /* CYRUS_SASL || TLS_SUPPORT */
if (pipe (pdi) == NOTOK)
return sm_ierror ("no pipes");
vecp = 0;
vec[vecp++] = r1bindex (sendmail, '/');
vec[vecp++] = "-bs";
-#ifndef ZMAILER
vec[vecp++] = watch ? "-odi" : queued ? "-odq" : "-odb";
vec[vecp++] = "-oem";
vec[vecp++] = "-om";
-# ifndef RAND
if (verbose)
vec[vecp++] = "-ov";
-# endif /* not RAND */
-#endif /* not ZMAILER */
vec[vecp++] = NULL;
setgid (getegid ());
return RP_RPLY;
}
- if (client && *client) {
- doingEHLO = 1;
- result = smtalk (SM_HELO, "EHLO %s", client);
- doingEHLO = 0;
+ doingEHLO = 1;
+ result = smtalk (SM_HELO, "EHLO %s", client);
+ doingEHLO = 0;
- if (500 <= result && result <= 599)
- result = smtalk (SM_HELO, "HELO %s", client);
+ if (500 <= result && result <= 599)
+ result = smtalk (SM_HELO, "HELO %s", client);
- switch (result) {
- case 250:
- break;
+ switch (result) {
+ case 250:
+ break;
- default:
- sm_end (NOTOK);
- return RP_RPLY;
- }
+ default:
+ sm_end (NOTOK);
+ return RP_RPLY;
}
-#ifndef ZMAILER
- if (onex)
- smtalk (SM_HELO, "ONEX");
-#endif
+#ifdef CYRUS_SASL
+ /*
+ * If the user asked for SASL, then check to see if the SMTP server
+ * supports it. Otherwise, error out (because the SMTP server
+ * might have been spoofed; we don't want to just silently not
+ * do authentication
+ */
+
+ if (sasl) {
+ if (! (server_mechs = EHLOset("AUTH"))) {
+ sm_end(NOTOK);
+ return sm_ierror("SMTP server does not support SASL");
+ }
+
+ if (saslmech && stringdex(saslmech, server_mechs) == -1) {
+ sm_end(NOTOK);
+ return sm_ierror("Requested SASL mech \"%s\" is not in the "
+ "list of supported mechanisms:\n%s",
+ saslmech, server_mechs);
+ }
+
+ if (sm_auth_sasl(user, saslssf, saslmech ? saslmech : server_mechs,
+ server) != RP_OK) {
+ sm_end(NOTOK);
+ return NOTOK;
+ }
+ }
+#endif /* CYRUS_SASL */
+
if (watch)
smtalk (SM_HELO, "VERB on");
}
int
-sm_winit (int mode, char *from)
+sm_winit (char *from)
{
- char *smtpcom;
-
- switch (mode) {
- case S_MAIL:
- smtpcom = "MAIL";
- break;
-
- case S_SEND:
- smtpcom = "SEND";
- break;
-
- case S_SOML:
- smtpcom = "SOML";
- break;
-
- case S_SAML:
- smtpcom = "SAML";
- break;
- }
-
- switch (smtalk (SM_MAIL, "%s FROM:<%s>", smtpcom, from)) {
+ switch (smtalk (SM_MAIL, "MAIL FROM:<%s>", from)) {
case 250:
sm_addrs = 0;
return RP_OK;
int status;
struct smtp sm_note;
- if (sm_mts == MTS_SENDMAIL) {
+ if (sm_mts == MTS_SENDMAIL_SMTP) {
switch (sm_child) {
case NOTOK:
case OK:
break;
}
+#ifdef TLS_SUPPORT
+ if (tls_active) {
+ BIO_ssl_shutdown(io);
+ BIO_free_all(io);
+ }
+#endif /* TLS_SUPPORT */
+
if (sm_rfp != NULL) {
alarm (SM_CLOS);
fclose (sm_rfp);
* (optionally) negotiated a security layer.
*/
static int
-sm_auth_sasl(char *user, char *mechlist, char *inhost)
+sm_auth_sasl(char *user, int saslssf, char *mechlist, char *inhost)
{
int result, status;
unsigned int buflen, outlen;
}
/*
- * Initialize the security properties
+ * Initialize the security properties. But if TLS is active, then
+ * don't negotiate encryption here.
*/
memset(&secprops, 0, sizeof(secprops));
secprops.maxbufsize = SASL_MAXRECVBUF;
- secprops.max_ssf = UINT_MAX;
+ secprops.max_ssf =
+ tls_active ? 0 : (saslssf != -1 ? (unsigned int) saslssf : UINT_MAX);
result = sasl_setprop(conn, SASL_SEC_PROPS, &secprops);
char *pass = NULL;
int len;
+ NMH_UNUSED (conn);
+
if (! psecret || id != SASL_CB_PASS)
return SASL_BADPARAM;
va_end(ap);
if (sm_debug) {
-#ifdef CYRUS_SASL
if (sasl_ssf)
- printf("(encrypted) ");
-#endif /* CYRUS_SASL */
+ printf("(sasl-encrypted) ");
+ if (tls_active)
+ printf("(tls-encrypted) ");
printf ("=> %s\n", buffer);
fflush (stdout);
}
const char *output;
unsigned int outputlen;
- if (sasl_complete == 0 || sasl_ssf == 0)
+ if (sasl_complete == 0 || sasl_ssf == 0) {
#endif /* CYRUS_SASL */
+#ifdef TLS_SUPPORT
+ if (tls_active) {
+ int ret;
+
+ ret = BIO_write(io, buffer, len);
+
+ if (ret <= 0) {
+ sm_ierror("TLS error during write: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ return NOTOK;
+ }
+ } else
+#endif /* TLS_SUPPORT */
fwrite(buffer, sizeof(*buffer), len, sm_wfp);
#ifdef CYRUS_SASL
- else {
+ } else {
while (len >= maxoutbuf - sasl_outbuflen) {
memcpy(sasl_outbuffer + sasl_outbuflen, buffer,
maxoutbuf - sasl_outbuflen);
}
#endif /* CYRUS_SASL */
+#ifdef TLS_SUPPORT
+ if (tls_active) {
+ (void) BIO_flush(io);
+ }
+#endif /* TLS_SUPPORT */
+
fflush(sm_wfp);
}
static int
smhear (void)
{
- int i, code, cont, bc, rc, more;
+ int i, code, cont, bc = 0, rc, more;
unsigned char *bp;
char *rp;
- char **ehlo, buffer[BUFSIZ];
+ char **ehlo = NULL, buffer[BUFSIZ];
if (doingEHLO) {
static int at_least_once = 0;
for (more = FALSE; sm_rrecord ((char *) (bp = (unsigned char *) buffer),
&bc) != NOTOK ; ) {
if (sm_debug) {
-#ifdef CYRUS_SASL
if (sasl_ssf > 0)
- printf("(decrypted) ");
-#endif /* CYRUS_SASL */
+ printf("(sasl-decrypted) ");
+ if (tls_active)
+ printf("(tls-decrypted) ");
printf ("<= %s\n", buffer);
fflush (stdout);
}
buffer[*len = 0] = 0;
if ((retval = sm_fgets (buffer, BUFSIZ, sm_rfp)) != RP_OK)
- return retval;
+ return sm_rerror (retval);
*len = strlen (buffer);
/* *len should be >0 except on EOF, but check for safety's sake */
if (*len == 0)
}
-#ifdef CYRUS_SASL
+#if defined(CYRUS_SASL) || defined(TLS_SUPPORT)
/*
- * Read from the network, but do SASL encryption
+ * Read from the network, but do SASL or TLS encryption
*/
static int
while (retbufsize == 0) {
+#ifdef TLS_SUPPORT
+ if (tls_active) {
+ cc = SSL_read(ssl, tmpbuf, sizeof(tmpbuf));
+
+ if (cc == 0) {
+ result = SSL_get_error(ssl, cc);
+
+ if (result != SSL_ERROR_ZERO_RETURN) {
+ sm_ierror("TLS peer aborted connection");
+ }
+
+ return EOF;
+ }
+
+ if (cc < 0) {
+ sm_ierror("SSL_read failed: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ return -2;
+ }
+ } else
+#endif /* TLS_SUPPORT */
+
cc = read(fileno(f), tmpbuf, sizeof(tmpbuf));
if (cc == 0)
* encryption working
*/
+#ifdef CYRUS_SASL
if (sasl_complete == 0 || sasl_ssf == 0) {
retbuf = tmpbuf;
retbufsize = cc;
return -2;
}
}
+#else /* ! CYRUS_SASL */
+ retbuf = tmpbuf;
+ retbufsize = cc;
+#endif /* CYRUS_SASL */
}
if (retbufsize > SASL_MAXRECVBUF) {
return (int) sasl_inbuffer[0];
}
-#endif /* CYRUS_SASL */
+#endif /* CYRUS_SASL || TLS_SUPPORT */
static int
sm_rerror (int rc)
}
-static RETSIGTYPE
+static void
alrmser (int i)
{
+ NMH_UNUSED (i);
+
#ifndef RELIABLE_SIGNALS
SIGNAL (SIGALRM, alrmser);
#endif
projects / mmh / blobdiff