Added NMH_ADDL_CPPFLAGS macro in new m4/cppflags.m4, to remove

[nmh] / mts / smtp / smtp.c

diff --git a/mts/smtp/smtp.c b/mts/smtp/smtp.c
index 3e8f32465e26ef9610e970baae455ca30f980514..79c1e79b4d0da2b5850cab8899c1a93be27edf37 100644 (file)
--- a/mts/smtp/smtp.c
+++ b/mts/smtp/smtp.c
@@ -10,6 +10,8 @@
 #include "smtp.h"
 #include <h/mts.h>
 #include <h/signals.h>
 #include "smtp.h"
 #include <h/mts.h>
 #include <h/signals.h>

+#include <h/utils.h>
+#include <h/oauth.h>

 
 #ifdef CYRUS_SASL
 #include <sasl/sasl.h>
 
 #ifdef CYRUS_SASL
 #include <sasl/sasl.h>


@@ -75,9 +77,7 @@
 #define        SM_DOT  600     /* see above */
 #define        SM_QUIT  30
 #define        SM_CLOS  10
 #define        SM_DOT  600     /* see above */
 #define        SM_QUIT  30
 #define        SM_CLOS  10

-#ifdef CYRUS_SASL

 #define        SM_AUTH  45
 #define        SM_AUTH  45

-#endif /* CYRUS_SASL */

 
 static int sm_addrs = 0;
 static int sm_alarmed = 0;
 
 static int sm_addrs = 0;
 static int sm_alarmed = 0;


@@ -89,15 +89,16 @@ static int sm_verbose = 0;
 static FILE *sm_rfp = NULL;
 static FILE *sm_wfp = NULL;
 
 static FILE *sm_rfp = NULL;
 static FILE *sm_wfp = NULL;
 

+static int next_line_encoded = 0;
+

 #ifdef CYRUS_SASL
 /*
  * Some globals needed by SASL
  */
 
 static sasl_conn_t *conn = NULL;       /* SASL connection state */
 #ifdef CYRUS_SASL
 /*
  * Some globals needed by SASL
  */
 
 static sasl_conn_t *conn = NULL;       /* SASL connection state */

-static int sasl_complete = 0;          /* Has authentication succeded? */
+static int sasl_complete = 0;          /* Has authentication succeeded? */

 static sasl_ssf_t sasl_ssf;            /* Our security strength factor */
 static sasl_ssf_t sasl_ssf;            /* Our security strength factor */

-static char *sasl_pw_context[3];       /* Context to pass into sm_get_pass */

 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 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 */


@@ -142,20 +143,19 @@ static int tls_active = 0;
 
 static char *sm_noreply = "No reply text given";
 static char *sm_moreply = "; ";
 
 static char *sm_noreply = "No reply text given";
 static char *sm_moreply = "; ";

-
-struct smtp sm_reply;          /* global... */
+static struct smtp sm_reply;

 
 #define        MAXEHLO 20
 
 static int doingEHLO;
 
 #define        MAXEHLO 20
 
 static int doingEHLO;

-char *EHLOkeys[MAXEHLO + 1];
+static char *EHLOkeys[MAXEHLO + 1];

 
 /*
  * static prototypes
  */
 
 /*
  * static prototypes
  */

-static int smtp_init (char *, char *, char *, int, int, int, int, int, int,
-                     char *, char *, int);
-static int sendmail_init (char *, char *, int, int, int, int, int, int,
+static int smtp_init (char *, char *, char *, int, int, int, int, int,
+                     char *, char *, const char *, int);
+static int sendmail_init (char *, char *, int, int, int, int, int,

                           char *, char *);
 
 static int rclient (char *, char *);
                           char *, char *);
 
 static int rclient (char *, char *);


@@ -169,11 +169,13 @@ static int sm_rrecord (char *, int *);
 static int sm_rerror (int);
 static void alrmser (int);
 static char *EHLOset (char *);
 static int sm_rerror (int);
 static void alrmser (int);
 static char *EHLOset (char *);

+static char *prepare_for_display (const char *, int *);

 static int sm_fwrite(char *, int);
 static int sm_fputs(char *);
 static int sm_fputc(int);
 static void sm_fflush(void);
 static int sm_fgets(char *, int, FILE *);
 static int sm_fwrite(char *, int);
 static int sm_fputs(char *);
 static int sm_fputc(int);
 static void sm_fflush(void);
 static int sm_fgets(char *, int, FILE *);

+static int sm_auth_xoauth2(const char *, const char *, int);

 
 #ifdef CYRUS_SASL
 /*
 
 #ifdef CYRUS_SASL
 /*


@@ -185,28 +187,26 @@ static int sm_auth_sasl(char *, int, char *, char *);
 
 int
 sm_init (char *client, char *server, char *port, int watch, int verbose,
 
 int
 sm_init (char *client, char *server, char *port, int watch, int verbose,

-         int debug, int queued, int sasl, int saslssf,
-        char *saslmech, char *user, int tls)
+         int debug, int sasl, int saslssf, char *saslmech, char *user,
+         const char *oauth_svc, int tls)

 {
     if (sm_mts == MTS_SMTP)
        return smtp_init (client, server, port, watch, verbose,
 {
     if (sm_mts == MTS_SMTP)
        return smtp_init (client, server, port, watch, verbose,

-                         debug, queued, sasl, saslssf, saslmech,
-                         user, tls);
+                         debug, sasl, saslssf, saslmech, user,
+                          oauth_svc, tls);

     else
        return sendmail_init (client, server, watch, verbose,
     else
        return sendmail_init (client, server, watch, verbose,

-                              debug, queued, sasl, saslssf, saslmech,
-                             user);
+                              debug, sasl, saslssf, saslmech, user);

 }
 
 static int
 smtp_init (char *client, char *server, char *port, int watch, int verbose,
 }
 
 static int
 smtp_init (char *client, char *server, char *port, int watch, int verbose,

-          int debug, int queued,
-           int sasl, int saslssf, char *saslmech, char *user, int tls)
+          int debug,
+           int sasl, int saslssf, char *saslmech, char *user,
+           const char *oauth_svc, int tls)

 {
     int result, sd1, sd2;
 {
     int result, sd1, sd2;

-#ifdef CYRUS_SASL
-    char *server_mechs;
-#else  /* CYRUS_SASL */
+#ifndef CYRUS_SASL

     NMH_UNUSED (sasl);
     NMH_UNUSED (saslssf);
     NMH_UNUSED (saslmech);
     NMH_UNUSED (sasl);
     NMH_UNUSED (saslssf);
     NMH_UNUSED (saslmech);


@@ -366,6 +366,7 @@ smtp_init (char *client, char *server, char *port, int watch, int verbose,
      */
 
     if (sasl) {
      */
 
     if (sasl) {

+        char *server_mechs;

        if (! (server_mechs = EHLOset("AUTH"))) {
            sm_end(NOTOK);
            return sm_ierror("SMTP server does not support SASL");
        if (! (server_mechs = EHLOset("AUTH"))) {
            sm_end(NOTOK);
            return sm_ierror("SMTP server does not support SASL");


@@ -378,7 +379,10 @@ smtp_init (char *client, char *server, char *port, int watch, int verbose,
                             saslmech, server_mechs);
        }
 
                             saslmech, server_mechs);
        }
 

-       if (sm_auth_sasl(user, saslssf, saslmech ? saslmech : server_mechs,
+        /* Don't call sm_auth_sasl() for XAUTH2 with -sasl.  Instead, call
+           sm_auth_xoauth2() below. */
+       if (oauth_svc == NULL  &&
+            sm_auth_sasl(user, saslssf, saslmech ? saslmech : server_mechs,

                         server) != RP_OK) {
            sm_end(NOTOK);
            return NOTOK;
                         server) != RP_OK) {
            sm_end(NOTOK);
            return NOTOK;


@@ -386,19 +390,29 @@ smtp_init (char *client, char *server, char *port, int watch, int verbose,
     }
 #endif /* CYRUS_SASL */
 
     }
 #endif /* CYRUS_SASL */
 

+    if (oauth_svc != NULL) {
+        char *server_mechs;
+       if ((server_mechs = EHLOset("AUTH")) == NULL
+            || stringdex("XOAUTH2", server_mechs) == -1) {
+           sm_end(NOTOK);
+           return sm_ierror("SMTP server does not support SASL XOAUTH2");
+       }
+       if (sm_auth_xoauth2(user, oauth_svc, debug) != RP_OK) {
+           sm_end(NOTOK);
+           return NOTOK;
+       }
+    }
+

 send_options: ;
     if (watch && EHLOset ("XVRB"))
        smtalk (SM_HELO, "VERB on");
 send_options: ;
     if (watch && EHLOset ("XVRB"))
        smtalk (SM_HELO, "VERB on");

-    if (queued && EHLOset ("XQUE"))
-       smtalk (SM_HELO, "QUED");

 
     return RP_OK;
 }
 
 int
 sendmail_init (char *client, char *server, int watch, int verbose,
 
     return RP_OK;
 }
 
 int
 sendmail_init (char *client, char *server, int watch, int verbose,

-               int debug, int queued,
-               int sasl, int saslssf, char *saslmech, char *user)
+               int debug, int sasl, int saslssf, char *saslmech, char *user)

 {
     unsigned int i, result, vecp;
     int pdi[2], pdo[2];
 {
     unsigned int i, result, vecp;
     int pdi[2], pdo[2];


@@ -474,15 +488,13 @@ sendmail_init (char *client, char *server, int watch, int verbose,
            vecp = 0;
            vec[vecp++] = r1bindex (sendmail, '/');
            vec[vecp++] = "-bs";
            vecp = 0;
            vec[vecp++] = r1bindex (sendmail, '/');
            vec[vecp++] = "-bs";

-           vec[vecp++] = watch ? "-odi" : queued ? "-odq" : "-odb";
+           vec[vecp++] = watch ? "-odi" : "-odb";

            vec[vecp++] = "-oem";
            vec[vecp++] = "-om";
            if (verbose)
                vec[vecp++] = "-ov";
            vec[vecp++] = NULL;
 
            vec[vecp++] = "-oem";
            vec[vecp++] = "-om";
            if (verbose)
                vec[vecp++] = "-ov";
            vec[vecp++] = NULL;
 

-           setgid (getegid ());
-           setuid (geteuid ());

            execvp (sendmail, vec);
            fprintf (stderr, "unable to exec ");
            perror (sendmail);
            execvp (sendmail, vec);
            fprintf (stderr, "unable to exec ");
            perror (sendmail);


@@ -808,17 +820,26 @@ sm_end (int type)
  * completes successfully, then authentication is successful and we've
  * (optionally) negotiated a security layer.
  */
  * completes successfully, then authentication is successful and we've
  * (optionally) negotiated a security layer.
  */

+
+#define CHECKB64SIZE(insize, outbuf, outsize) \
+    { size_t wantout = (((insize + 2) / 3) * 4) + 32; \
+      if (wantout > outsize) { \
+          outbuf = mh_xrealloc(outbuf, outsize = wantout); \
+      } \
+    }
+

 static int
 sm_auth_sasl(char *user, int saslssf, char *mechlist, char *inhost)
 {
     int result, status;
     unsigned int buflen, outlen;
 static int
 sm_auth_sasl(char *user, int saslssf, char *mechlist, char *inhost)
 {
     int result, status;
     unsigned int buflen, outlen;

-    char *buf, outbuf[BUFSIZ], host[NI_MAXHOST];
+    char *buf, *outbuf = NULL, host[NI_MAXHOST];

     const char *chosen_mech;
     sasl_security_properties_t secprops;
     sasl_ssf_t *ssf;
     int *outbufmax;
     const char *chosen_mech;
     sasl_security_properties_t secprops;
     sasl_ssf_t *ssf;
     int *outbufmax;

-    char *pass = NULL;
+    struct nmh_creds creds = { 0, 0, 0 };
+    size_t outbufsize = 0;

 
     /*
      * Initialize the callback contexts
 
     /*
      * Initialize the callback contexts


@@ -854,14 +875,13 @@ sm_auth_sasl(char *user, int saslssf, char *mechlist, char *inhost)
        strncpy(host, inhost, sizeof(host) - 1);
     }
 
        strncpy(host, inhost, sizeof(host) - 1);
     }
 

-    callbacks[SM_SASL_N_CB_USER].context = user;
-    callbacks[SM_SASL_N_CB_AUTHNAME].context = user;
-
-    sasl_pw_context[0] = host;
-    sasl_pw_context[1] = user;
-    sasl_pw_context[2] = pass;
-
-    callbacks[SM_SASL_N_CB_PASS].context = sasl_pw_context;
+    /* It's OK to copy the addresses here.  The callbacks that use
+       them will only be called before this function returns. */
+    creds.host = host;
+    creds.user = user;
+    callbacks[SM_SASL_N_CB_USER].context = &creds;
+    callbacks[SM_SASL_N_CB_AUTHNAME].context = &creds;
+    callbacks[SM_SASL_N_CB_PASS].context = &creds;

 
     result = sasl_client_init(callbacks);
 
 
     result = sasl_client_init(callbacks);
 


@@ -916,10 +936,13 @@ sm_auth_sasl(char *user, int saslssf, char *mechlist, char *inhost)
      */
 
     if (buflen) {
      */
 
     if (buflen) {

-       status = sasl_encode64(buf, buflen, outbuf, sizeof(outbuf), NULL);
+       CHECKB64SIZE(buflen, outbuf, outbufsize);
+       status = sasl_encode64(buf, buflen, outbuf, outbufsize, NULL);

        if (status != SASL_OK) {
            sm_ierror("SASL base64 encode failed: %s",
                      sasl_errstring(status, NULL, NULL));
        if (status != SASL_OK) {
            sm_ierror("SASL base64 encode failed: %s",
                      sasl_errstring(status, NULL, NULL));

+           if (outbuf)
+               free(outbuf);

            return NOTOK;
        }
 
            return NOTOK;
        }
 


@@ -946,8 +969,11 @@ sm_auth_sasl(char *user, int saslssf, char *mechlist, char *inhost)
 
        if (status == 235)
            break;
 
        if (status == 235)
            break;

-       else if (status < 300 || status > 399)
+       else if (status < 300 || status > 399) {
+           if (outbuf)
+               free(outbuf);

            return RP_BHST;
            return RP_BHST;

+       }

        
        /*
         * Special case; a zero-length response from the SMTP server
        
        /*
         * Special case; a zero-length response from the SMTP server


@@ -958,13 +984,18 @@ sm_auth_sasl(char *user, int saslssf, char *mechlist, char *inhost)
        if (strcmp("=", sm_reply.text) == 0) {
            outlen = 0;
        } else {
        if (strcmp("=", sm_reply.text) == 0) {
            outlen = 0;
        } else {

+           if (sm_reply.length > (int) outbufsize) {
+               outbuf = mh_xrealloc(outbuf, outbufsize = sm_reply.length);
+           }
+

            result = sasl_decode64(sm_reply.text, sm_reply.length,
            result = sasl_decode64(sm_reply.text, sm_reply.length,

-                                  outbuf, sizeof(outbuf), &outlen);
-       
+                                  outbuf, outbufsize, &outlen);

            if (result != SASL_OK) {
                smtalk(SM_AUTH, "*");
                sm_ierror("SASL base64 decode failed: %s",
                          sasl_errstring(result, NULL, NULL));
            if (result != SASL_OK) {
                smtalk(SM_AUTH, "*");
                sm_ierror("SASL base64 decode failed: %s",
                          sasl_errstring(result, NULL, NULL));

+               if (outbuf)
+                   free(outbuf);

                return NOTOK;
            }
        }
                return NOTOK;
            }
        }


@@ -976,21 +1007,29 @@ sm_auth_sasl(char *user, int saslssf, char *mechlist, char *inhost)
            smtalk(SM_AUTH, "*");
            sm_ierror("SASL client negotiation failed: %s",
                      sasl_errstring(result, NULL, NULL));
            smtalk(SM_AUTH, "*");
            sm_ierror("SASL client negotiation failed: %s",
                      sasl_errstring(result, NULL, NULL));

+           if (outbuf)
+               free(outbuf);

            return NOTOK;
        }
 
            return NOTOK;
        }
 

-       status = sasl_encode64(buf, buflen, outbuf, sizeof(outbuf), NULL);
+       CHECKB64SIZE(buflen, outbuf, outbufsize);
+       status = sasl_encode64(buf, buflen, outbuf, outbufsize, NULL);

 
        if (status != SASL_OK) {
            smtalk(SM_AUTH, "*");
            sm_ierror("SASL base64 encode failed: %s",
                      sasl_errstring(status, NULL, NULL));
 
        if (status != SASL_OK) {
            smtalk(SM_AUTH, "*");
            sm_ierror("SASL base64 encode failed: %s",
                      sasl_errstring(status, NULL, NULL));

+           if (outbuf)
+               free(outbuf);

            return NOTOK;
        }
        
        status = smtalk(SM_AUTH, outbuf);
     }
 
            return NOTOK;
        }
        
        status = smtalk(SM_AUTH, outbuf);
     }
 

+    if (outbuf)
+       free(outbuf);
+

     /*
      * Make sure that we got the correct response
      */
     /*
      * Make sure that we got the correct response
      */


@@ -1052,14 +1091,27 @@ sm_auth_sasl(char *user, int saslssf, char *mechlist, char *inhost)
 static int
 sm_get_user(void *context, int id, const char **result, unsigned *len)
 {
 static int
 sm_get_user(void *context, int id, const char **result, unsigned *len)
 {

-    char *user = (char *) context;
+    nmh_creds_t creds = (nmh_creds_t) context;

 
     if (! result || ((id != SASL_CB_USER) && (id != SASL_CB_AUTHNAME)))
        return SASL_BADPARAM;
 
 
     if (! result || ((id != SASL_CB_USER) && (id != SASL_CB_AUTHNAME)))
        return SASL_BADPARAM;
 

-    *result = user;
+    if (creds->user == NULL) {
+        /*
+         * Pass the 1 third argument to nmh_get_credentials() so
+         * that a default user if the -user switch to send(1)/post(8)
+         * wasn't used, and so that a default password will be supplied.
+         * That's used when those values really don't matter, and only
+         * with legacy/.netrc, i.e., with a credentials profile entry.
+         */
+        if (nmh_get_credentials (creds->host, creds->user, 1, creds) != OK) {
+            return SASL_BADPARAM;
+        }
+    }
+
+    *result = creds->user;

     if (len)
     if (len)

-       *len = strlen(user);
+       *len = strlen(creds->user);

 
     return SASL_OK;
 }
 
     return SASL_OK;
 }


@@ -1068,7 +1120,7 @@ static int
 sm_get_pass(sasl_conn_t *conn, void *context, int id,
            sasl_secret_t **psecret)
 {
 sm_get_pass(sasl_conn_t *conn, void *context, int id,
            sasl_secret_t **psecret)
 {

-    char **pw_context = (char **) context;
+    nmh_creds_t creds = (nmh_creds_t) context;

     int len;
 
     NMH_UNUSED (conn);
     int len;
 
     NMH_UNUSED (conn);


@@ -1076,19 +1128,78 @@ sm_get_pass(sasl_conn_t *conn, void *context, int id,
     if (! psecret || id != SASL_CB_PASS)
        return SASL_BADPARAM;
 
     if (! psecret || id != SASL_CB_PASS)
        return SASL_BADPARAM;
 

-    len = strlen (pw_context[2]);
+    if (creds->password == NULL) {
+        /*
+         * Pass the 0 third argument to nmh_get_credentials() so
+         * that the default password isn't used.  With legacy/.netrc
+         * credentials support, we'll only get here if the -user
+         * switch to send(1)/post(8) wasn't used.
+         */
+        if (nmh_get_credentials (creds->host, creds->user, 0, creds) != OK) {
+            return SASL_BADPARAM;
+        }
+    }
+
+    len = strlen (creds->password);

 
     if (! (*psecret = (sasl_secret_t *) malloc(sizeof(sasl_secret_t) + len))) {
        return SASL_NOMEM;
     }
 
     (*psecret)->len = len;
 
     if (! (*psecret = (sasl_secret_t *) malloc(sizeof(sasl_secret_t) + len))) {
        return SASL_NOMEM;
     }
 
     (*psecret)->len = len;

-    strcpy((char *) (*psecret)->data, pw_context[2]);
+    strcpy((char *) (*psecret)->data, creds->password);

 
     return SASL_OK;
 }
 #endif /* CYRUS_SASL */
 
 
     return SASL_OK;
 }
 #endif /* CYRUS_SASL */
 

+/* https://developers.google.com/gmail/xoauth2_protocol */
+static int
+sm_auth_xoauth2(const char *user, const char *oauth_svc, int snoop)
+{
+    const char *xoauth_client_res;
+    int status;
+
+#ifdef OAUTH_SUPPORT
+    xoauth_client_res = mh_oauth_do_xoauth(user, oauth_svc,
+                                          snoop ? stderr : NULL);
+
+    if (xoauth_client_res == NULL) {
+       return sm_ierror("Internal error: mh_oauth_do_xoauth() returned NULL");
+    }
+#else
+    NMH_UNUSED(user);
+    NMH_UNUSED(snoop);
+    adios(NULL, "sendfrom built without OAUTH_SUPPORT, "
+          "so oauth_svc %s is not supported", oauth_svc);
+#endif /* OAUTH_SUPPORT */
+
+    status = smtalk(SM_AUTH, "AUTH XOAUTH2 %s", xoauth_client_res);
+    if (status == 235) {
+        /* It worked! */
+        return RP_OK;
+    }
+
+    /*
+     * Status is 334 and sm_reply.text contains base64-encoded JSON.  As far as
+     * epg can tell, no matter the error, the JSON is always the same:
+     * {"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"}
+     * I tried these errors:
+     * - garbage token
+     * - expired token
+     * - wrong scope
+     * - wrong username
+     */
+    /* Then we're supposed to send an empty response ("\r\n"). */
+    smtalk(SM_AUTH, "");
+    /*
+     * And now we always get this, again, no matter the error:
+     * 535-5.7.8 Username and Password not accepted. Learn more at
+     * 535 5.7.8 http://support.google.com/mail/bin/answer.py?answer=14257
+     */
+    return RP_BHST;
+}
+

 static int
 sm_ierror (char *fmt, ...)
 {
 static int
 sm_ierror (char *fmt, ...)
 {


@@ -1109,18 +1220,32 @@ smtalk (int time, char *fmt, ...)
 {
     va_list ap;
     int result;
 {
     va_list ap;
     int result;

-    char buffer[BUFSIZ];
+    char *buffer;
+    size_t bufsize = BUFSIZ;
+
+    buffer = mh_xmalloc(bufsize);

 
     va_start(ap, fmt);
 
     va_start(ap, fmt);

-    vsnprintf (buffer, sizeof(buffer), fmt, ap);
+    result = vsnprintf (buffer, bufsize, fmt, ap);

     va_end(ap);
 
     va_end(ap);
 

+    if (result > (int) bufsize) {
+       buffer = mh_xrealloc(buffer, bufsize = result + 1);
+       va_start(ap, fmt);
+       vsnprintf (buffer, bufsize, fmt, ap);
+       va_end(ap);
+    }
+

     if (sm_debug) {
     if (sm_debug) {

+       char *decoded_buffer =
+            prepare_for_display (buffer, &next_line_encoded);
+

        if (sasl_ssf)
                printf("(sasl-encrypted) ");
        if (tls_active)
                printf("(tls-encrypted) ");
        if (sasl_ssf)
                printf("(sasl-encrypted) ");
        if (tls_active)
                printf("(tls-encrypted) ");

-       printf ("=> %s\n", buffer);
+       printf ("=> %s\n", decoded_buffer);
+       free (decoded_buffer);

        fflush (stdout);
     }
 
        fflush (stdout);
     }
 


@@ -1130,6 +1255,8 @@ smtalk (int time, char *fmt, ...)
        result = smhear ();
     alarm (0);
 
        result = smhear ();
     alarm (0);
 

+    free(buffer);
+

     return result;
 }
 
     return result;
 }
 


@@ -1168,7 +1295,7 @@ sm_wstream (char *buffer, int len)
        return (ferror (sm_wfp) ? sm_werror () : OK);
     }
 
        return (ferror (sm_wfp) ? sm_werror () : OK);
     }
 

-    for (bp = buffer; len > 0; bp++, len--) {
+    for (bp = buffer; bp && len > 0; bp++, len--) {

        switch (*bp) {
            case '\n': 
                sm_nl = TRUE;
        switch (*bp) {
            case '\n': 
                sm_nl = TRUE;


@@ -1217,7 +1344,9 @@ sm_fwrite(char *buffer, int len)
            }
        } else
 #endif /* TLS_SUPPORT */
            }
        } else
 #endif /* TLS_SUPPORT */

-       fwrite(buffer, sizeof(*buffer), len, sm_wfp);
+       if ((int) fwrite(buffer, sizeof(*buffer), len, sm_wfp) < len) {
+           advise ("sm_fwrite", "fwrite");
+       }

 #ifdef CYRUS_SASL
     } else {
        while (len >= maxoutbuf - sasl_outbuflen) {
 #ifdef CYRUS_SASL
     } else {
        while (len >= maxoutbuf - sasl_outbuflen) {


@@ -1233,7 +1362,10 @@ sm_fwrite(char *buffer, int len)
                return NOTOK;
            }
 
                return NOTOK;
            }
 

-           fwrite(output, sizeof(*output), outputlen, sm_wfp);
+           if (fwrite(output, sizeof(*output), outputlen, sm_wfp) <
+               outputlen) {
+               advise ("sm_fwrite", "fwrite");
+           }

        }
 
        if (len > 0) {
        }
 
        if (len > 0) {


@@ -1342,7 +1474,7 @@ tls_negotiate(void)
 #endif /* TLS_SUPPORT */
 
 /*
 #endif /* TLS_SUPPORT */
 
 /*

- * Convenience functions to replace occurences of fputs() and fputc()
+ * Convenience functions to replace occurrences of fputs() and fputc()

  */
 
 static int
  */
 
 static int


@@ -1380,7 +1512,9 @@ sm_fflush(void)
            return;
        }
 
            return;
        }
 

-       fwrite(output, sizeof(*output), outputlen, sm_wfp);
+       if (fwrite(output, sizeof(*output), outputlen, sm_wfp) < outputlen) {
+           advise ("sm_fflush", "fwrite");
+       }

        sasl_outbuflen = 0;
     }
 #endif /* CYRUS_SASL */
        sasl_outbuflen = 0;
     }
 #endif /* CYRUS_SASL */


@@ -1412,7 +1546,7 @@ smhear (void)
     int i, code, cont, bc = 0, rc, more;
     unsigned char *bp;
     char *rp;
     int i, code, cont, bc = 0, rc, more;
     unsigned char *bp;
     char *rp;

-    char **ehlo = NULL, buffer[BUFSIZ];
+    char **ehlo = EHLOkeys, buffer[BUFSIZ];

 
     if (doingEHLO) {
        static int at_least_once = 0;
 
     if (doingEHLO) {
        static int at_least_once = 0;


@@ -1442,11 +1576,15 @@ again: ;
     for (more = FALSE; sm_rrecord ((char *) (bp = (unsigned char *) buffer),
                                   &bc) != NOTOK ; ) {
        if (sm_debug) {
     for (more = FALSE; sm_rrecord ((char *) (bp = (unsigned char *) buffer),
                                   &bc) != NOTOK ; ) {
        if (sm_debug) {

+           char *decoded_buffer =
+                prepare_for_display (buffer, &next_line_encoded);
+

            if (sasl_ssf > 0)
                printf("(sasl-decrypted) ");
            if (tls_active)
                printf("(tls-decrypted) ");
            if (sasl_ssf > 0)
                printf("(sasl-decrypted) ");
            if (tls_active)
                printf("(tls-decrypted) ");

-           printf ("<= %s\n", buffer);
+           printf ("<= %s\n", decoded_buffer);
+           free (decoded_buffer);

            fflush (stdout);
        }
 
            fflush (stdout);
        }
 


@@ -1788,3 +1926,69 @@ EHLOset (char *s)
 
     return 0;
 }
 
     return 0;
 }

+
+
+/*
+ * Detects, using heuristics, if an SMTP server or client response string
+ * contains a base64-encoded portion.  If it does, decodes it and replaces
+ * any non-printable characters with a hex representation.  Caller is
+ * responsible for free'ing return value.  If the decode fails, a copy of
+ * the input string is returned.
+ */
+static
+char *
+prepare_for_display (const char *string, int *next_line_encoded) {
+    const char *start = NULL;
+    const char *decoded;
+    size_t decoded_len;
+    int prefix_len = -1;
+
+    if (strncmp (string, "AUTH ", 5) == 0) {
+        /* AUTH line:  the mechanism isn't encoded.  If there's an initial
+           response, it must be base64 encoded.. */
+        char *mechanism = strchr (string + 5, ' ');
+
+        if (mechanism != NULL) {
+            prefix_len = (int) (mechanism - string + 1);
+        } /* else no space following the mechanism, so no initial response */
+        *next_line_encoded = 0;
+    } else if (strncmp (string, "334 ", 4) == 0) {
+        /* 334 is the server's request for user or password. */
+        prefix_len = 4;
+        /* The next (client response) line must be base64 encoded. */
+        *next_line_encoded = 1;
+    } else if (*next_line_encoded) {
+        /* "next" line now refers to this line, which is a base64-encoded
+           client response. */
+        prefix_len = 0;
+        *next_line_encoded = 0;
+    } else {
+        *next_line_encoded = 0;
+    }
+
+    /* Don't attempt to decoded unencoded initial response ('=') or cancel
+       response ('*'). */
+    if (prefix_len > -1  &&
+        string[prefix_len] != '='  &&  string[prefix_len] != '*') {
+        start = string + prefix_len;
+    }
+
+    if (start  &&  decodeBase64 (start, &decoded, &decoded_len, 1, NULL) == OK) {
+        char *hexified;
+        char *prefix = mh_xmalloc(prefix_len + 1);
+        char *display_string;
+
+        /* prefix is the beginning portion, which isn't base64 encoded. */
+        snprintf (prefix, prefix_len + 1, "%*s", prefix_len, string);
+        hexify ((const unsigned char *) decoded, decoded_len, &hexified);
+        /* Wrap the decoded portion in "b64<>". */
+        display_string = concat (prefix, "b64<", hexified, ">", NULL);
+        free (hexified);
+        free (prefix);
+        free ((char *) decoded);
+
+        return display_string;
+    } else {
+        return getcpy (string);
+    }
+}