X-Git-Url: https://diplodocus.org/git/nmh/blobdiff_plain/4ea2f92f36fcf39727438cd55580c99a5a6e6ad8..44c4b1b168d0ac7c860f91495c423f425e8a87d9:/sbr/netsec.c

diff --git a/sbr/netsec.c b/sbr/netsec.c
index 372732c3..895892a2 100644
--- a/sbr/netsec.c
+++ b/sbr/netsec.c
@@ -54,8 +54,12 @@ static SSL_CTX *sslctx = NULL;		/* SSL Context */
  */
 
 struct _netsec_context {
-    int ns_fd;			/* Descriptor for network connection */
+    int ns_readfd;		/* Read descriptor for network connection */
+    int ns_writefd;		/* Write descriptor for network connection */
     int ns_snoop;		/* If true, display network data */
+    int ns_snoop_noend;		/* If true, didn't get a CR/LF on last line */
+    netsec_snoop_callback *ns_snoop_cb; /* Snoop output callback */
+    void *ns_snoop_context;	/* Context data for snoop function */
     int ns_timeout;		/* Network read timeout, in seconds */
     char *ns_userid;		/* Userid for authentication */
     unsigned char *ns_inbuffer;	/* Our read input buffer */
@@ -89,12 +93,6 @@ struct _netsec_context {
 #endif /* TLS_SUPPORT */
 };
 
-/*
- * Function to allocate error message strings
- */
-
-static void netsec_err(char **errstr, const char *format, ...);
-
 /*
  * Function to read data from the actual network socket
  */
@@ -126,8 +124,12 @@ netsec_init(void)
 {
     netsec_context *nsc = mh_xmalloc(sizeof(*nsc));
 
-    nsc->ns_fd = -1;
+    nsc->ns_readfd = -1;
+    nsc->ns_writefd = -1;
     nsc->ns_snoop = 0;
+    nsc->ns_snoop_noend = 0;
+    nsc->ns_snoop_cb = NULL;
+    nsc->ns_snoop_context = NULL;
     nsc->ns_userid = NULL;
     nsc->ns_timeout = 60;	/* Our default */
     nsc->ns_inbufsize = NETSEC_BUFSIZE;
@@ -214,8 +216,12 @@ netsec_shutdown(netsec_context *nsc, int closeflag)
 	BIO_free_all(nsc->ssl_io);
 #endif /* TLS_SUPPORT */
 
-    if (closeflag && nsc->ns_fd != -1)
-	close(nsc->ns_fd);
+    if (closeflag) {
+	if (nsc->ns_readfd != -1)
+	    close(nsc->ns_readfd);
+	if (nsc->ns_writefd != -1 && nsc->ns_writefd != nsc->ns_readfd)
+	    close(nsc->ns_writefd);
+    }
 
     free(nsc);
 }
@@ -225,9 +231,10 @@ netsec_shutdown(netsec_context *nsc, int closeflag)
  */
 
 void
-netsec_set_fd(netsec_context *nsc, int fd)
+netsec_set_fd(netsec_context *nsc, int readfd, int writefd)
 {
-    nsc->ns_fd = fd;
+    nsc->ns_readfd = readfd;
+    nsc->ns_writefd = writefd;
 }
 
 /*
@@ -260,6 +267,52 @@ netsec_set_snoop(netsec_context *nsc, int snoop)
     nsc->ns_snoop = snoop;
 }
 
+/*
+ * Set the snoop callback for this connection.
+ */
+
+void netsec_set_snoop_callback(netsec_context *nsc,
+			       netsec_snoop_callback callback, void *context)
+{
+    nsc->ns_snoop_cb = callback;
+    nsc->ns_snoop_context = context;
+}
+
+/*
+ * A base64-decoding snoop callback
+ */
+
+void
+netsec_b64_snoop_decoder(netsec_context *nsc, const char *string, size_t len,
+			 void *context)
+{
+    const char *decoded;
+    size_t decodedlen;
+    NMH_UNUSED(nsc);
+    int offset;
+
+    offset = context ? *((int *) context) : 0;
+
+    if (offset > 0) {
+	/*
+	 * Output non-base64 data first.
+	 */
+	fprintf(stderr, "%.*s", offset, string);
+	string += offset;
+	len -= offset;
+    }
+
+    if (decodeBase64(string, &decoded, &decodedlen, 1, NULL) == OK) {
+	char *hexified;
+	hexify((const unsigned char *) decoded, decodedlen, &hexified);
+	fprintf(stderr, "b64<%s>\n", hexified);
+	free(hexified);
+	free((char *) decoded);
+    } else {
+	fprintf(stderr, "%.*s\n", (int) len, string);
+    }
+}
+
 /*
  * Set the read timeout for this connection
  */
@@ -327,7 +380,7 @@ netsec_read(netsec_context *nsc, void *buffer, size_t size, char **errstr)
  */
 
 char *
-netsec_readline(netsec_context *nsc, char **errstr)
+netsec_readline(netsec_context *nsc, size_t *len, char **errstr)
 {
     unsigned char *ptr = nsc->ns_inptr;
     size_t count = 0, offset;
@@ -344,8 +397,26 @@ retry:
 	    if (count > 1 && *(ptr - 2) == '\r')
 		ptr--;
 	    *--ptr = '\0';
+	    if (len)
+		*len = ptr - nsc->ns_inptr;
 	    nsc->ns_inptr += count;
 	    nsc->ns_inbuflen -= count;
+	    if (nsc->ns_snoop) {
+#ifdef CYRUS_SASL
+		if (nsc->sasl_seclayer)
+		    fprintf(stderr, "(sasl-decrypted) ");
+#endif /* CYRUS_SASL */
+#ifdef TLS_SUPPORT
+		if (nsc->tls_active)
+		    fprintf(stderr, "(tls-decrypted) ");
+#endif /* TLS_SUPPORT */
+		fprintf(stderr, "<= ");
+		if (nsc->ns_snoop_cb)
+		    nsc->ns_snoop_cb(nsc, sptr, strlen(sptr),
+				     nsc->ns_snoop_context);
+		else
+		    fprintf(stderr, "%s\n", sptr);
+	    }
 	    return sptr;
 	}
     }
@@ -412,12 +483,12 @@ retry:
 	fd_set rfds;
 
 	FD_ZERO(&rfds);
-	FD_SET(nsc->ns_fd, &rfds);
+	FD_SET(nsc->ns_readfd, &rfds);
 
 	tv.tv_sec = nsc->ns_timeout;
 	tv.tv_usec = 0;
 
-	rc = select(nsc->ns_fd + 1, &rfds, NULL, NULL, &tv);
+	rc = select(nsc->ns_readfd + 1, &rfds, NULL, NULL, &tv);
 
 	if (rc == -1) {
 	    netsec_err(errstr, "select() while reading failed: %s",
@@ -489,7 +560,7 @@ retry:
      * select() above) so this read SHOULDN'T block.  Hopefully.
      */
 
-    rc = read(nsc->ns_fd, readbuf, readbufsize);
+    rc = read(nsc->ns_readfd, readbuf, readbufsize);
 
     if (rc == 0) {
 	netsec_err(errstr, "Received EOF on network read");
@@ -567,24 +638,10 @@ netsec_write(netsec_context *nsc, const void *buffer, size_t size,
     const unsigned char *bufptr = buffer;
     int rc, remaining;
 
-    /*
-     * If TLS is active, then bypass all of our buffering logic; just
-     * write it directly to our BIO.  We have a buffering BIO first in
-     * our stack, so buffering will take place there.
-     */
-#ifdef TLS_SUPPORT
-    if (nsc->tls_active) {
-	rc = BIO_write(nsc->ssl_io, buffer, size);
-
-	if (rc <= 0) {
-	    netsec_err(errstr, "Error writing to TLS connection: %s",
-		       ERR_error_string(ERR_get_error(), NULL));
-	    return NOTOK;
-	}
+    /* Just in case */
 
+    if (size == 0)
 	return OK;
-    }
-#endif /* TLS_SUPPORT */
 
     /*
      * Run a loop copying in data to our local buffer; when we're done with
@@ -624,6 +681,7 @@ netsec_write(netsec_context *nsc, const void *buffer, size_t size,
 
 /*
  * Our network printf() routine, which really just calls netsec_vprintf().
+ */
 
 int
 netsec_printf(netsec_context *nsc, char **errstr, const char *format, ...)
@@ -631,7 +689,7 @@ netsec_printf(netsec_context *nsc, char **errstr, const char *format, ...)
     va_list ap;
     int rc;
 
-    va_start(format, ap);
+    va_start(ap, format);
     rc = netsec_vprintf(nsc, errstr, format, ap);
     va_end(ap);
 
@@ -651,23 +709,6 @@ netsec_vprintf(netsec_context *nsc, char **errstr, const char *format,
 {
     int rc;
 
-    /*
-     * Again, if we're using TLS, then bypass our local buffering
-     */
-#ifdef TLS_SUPPORT
-    if (nsc->tls_active) {
-	rc = BIO_vprintf(nsc->ssl_io, format, ap);
-
-	if (rc <= 0) {
-	    netsec_err(errstr, "Error writing to TLS connection: %s",
-		       ERR_error_string(ERR_get_error(), NULL));
-	    return NOTOK;
-	}
-
-	return OK;
-    }
-#endif /* TLS_SUPPORT */
-
     /*
      * Cheat a little.  If we can fit the data into our outgoing buffer,
      * great!  If not, generate a flush and retry once.
@@ -709,6 +750,35 @@ retry:
 	}
     }
 
+    if (nsc->ns_snoop) {
+	int outlen = rc;
+	if (outlen > 0 && nsc->ns_outptr[outlen - 1] == '\n') {
+	    outlen--;
+	    if (outlen > 0 && nsc->ns_outptr[outlen - 1] == '\r')
+		outlen--;
+	} else {
+	    nsc->ns_snoop_noend = 1;
+	}
+	if (outlen > 0 || nsc->ns_snoop_noend == 0) {
+#ifdef CYRUS_SASL
+	    if (nsc->sasl_seclayer)
+		fprintf(stderr, "(sasl-encrypted) ");
+#endif /* CYRUS_SASL */
+#ifdef TLS_SUPPORT
+	    if (nsc->tls_active)
+		fprintf(stderr, "(tls-encrypted) ");
+#endif /* TLS_SUPPORT */
+	    fprintf(stderr, "=> ");
+	    if (nsc->ns_snoop_cb)
+		nsc->ns_snoop_cb(nsc, (char *) nsc->ns_outptr, outlen,
+				 nsc->ns_snoop_context);
+	    else
+		 fprintf(stderr, "%.*s\n", outlen, nsc->ns_outptr); 
+	} else {
+	    nsc->ns_snoop_noend = 0;
+	}
+    }
+
     nsc->ns_outptr += rc;
     nsc->ns_outbuflen += rc;
 
@@ -728,26 +798,15 @@ netsec_flush(netsec_context *nsc, char **errstr)
     int rc;
 
     /*
-     * For TLS connections, just call BIO_flush(); we'll let TLS handle
-     * all of our output buffering.
+     * Small optimization
      */
-#ifdef TLS_SUPPORT
-    if (nsc->tls_active) {
-	rc = BIO_flush(nsc->ssl_io);
-
-	if (rc <= 0) {
-	    netsec_err(errstr, "Error flushing TLS connection: %s",
-		       ERR_error_string(ERR_get_error(), NULL));
-	    return NOTOK;
-	}
 
+    if (netoutlen == 0)
 	return OK;
-    }
-#endif /* TLS_SUPPORT */
 
     /*
      * If SASL security layers are in effect, run the data through
-     * sasl_encode() first and then write it.
+     * sasl_encode() first.
      */
 #ifdef CYRUS_SASL
     if (nsc->sasl_seclayer) {
@@ -762,11 +821,27 @@ netsec_flush(netsec_context *nsc, char **errstr)
 
     }
 #endif /* CYRUS_SASL */
-    rc = write(nsc->ns_fd, netoutbuf, netoutlen);
 
-    if (rc < 0) {
-	netsec_err(errstr, "write() failed: %s", strerror(errno));
-	return NOTOK;
+    /*
+     * If TLS is active, then use those functions to write out the
+     * data.
+     */
+#ifdef TLS_SUPPORT
+    if (nsc->tls_active) {
+	if (BIO_write(nsc->ssl_io, netoutbuf, netoutlen) <= 0) {
+	    netsec_err(errstr, "Error writing to TLS connection: %s",
+		       ERR_error_string(ERR_get_error(), NULL));
+	    return NOTOK;
+	}
+    } else
+#endif /* TLS_SUPPORT */
+    {
+	rc = write(nsc->ns_writefd, netoutbuf, netoutlen);
+
+	if (rc < 0) {
+	    netsec_err(errstr, "write() failed: %s", strerror(errno));
+	    return NOTOK;
+	}
     }
 
     nsc->ns_outptr = nsc->ns_outbuffer;
@@ -832,7 +907,21 @@ netsec_set_sasl_params(netsec_context *nsc, const char *hostname,
 	return NOTOK;
     }
 
-    nsc->sasl_mech = mechanism ? getcpy(mechanism) : NULL;
+    /*
+     * According to the RFC, mechanisms can only be uppercase letter, numbers,
+     * and a hypen or underscore.  So make sure we uppercase any letters
+     * in case the user passed in lowercase.
+     */
+
+    if (mechanism) {
+	char *p;
+	nsc->sasl_mech = getcpy(mechanism);
+
+	for (p = nsc->sasl_mech; *p; p++)
+	    if (isascii((unsigned char) *p))	/* Just in case */
+		*p = toupper((unsigned char) *p);
+    }
+
     nsc->sasl_proto_cb = callback;
     nsc->sasl_hostname = getcpy(hostname);
 
@@ -965,7 +1054,8 @@ netsec_negotiate_sasl(netsec_context *nsc, const char *mechlist, char **errstr)
     int *outbufmax;
 #endif
 #ifdef OAUTH_SUPPORT
-    const char *xoauth_client_res;
+    unsigned char *xoauth_client_res;
+    size_t xoauth_client_res_len;
 #endif /* OAUTH_SUPPORT */
     int rc;
 
@@ -988,7 +1078,6 @@ netsec_negotiate_sasl(netsec_context *nsc, const char *mechlist, char **errstr)
 
 	i = (str[i] == NULL);
 
-	free(str);
 	free(mlist);
 
 	if (i) {
@@ -999,11 +1088,11 @@ netsec_negotiate_sasl(netsec_context *nsc, const char *mechlist, char **errstr)
     }
 
 #ifdef OAUTH_SUPPORT
-    if (strcasecmp(nsc->sasl_mech, "XOAUTH2") == 0) {
+    if (nsc->sasl_mech && strcasecmp(nsc->sasl_mech, "XOAUTH2") == 0) {
 	/*
 	 * This should be relatively straightforward, but requires some
 	 * help from the plugin.  Basically, if XOAUTH2 is a success,
-	 * the plugin has to return success, but no output data.  If
+	 * the callback has to return success, but no output data.  If
 	 * there is output data, it will be assumed that it is the JSON
 	 * error message.
 	 */
@@ -1015,19 +1104,46 @@ netsec_negotiate_sasl(netsec_context *nsc, const char *mechlist, char **errstr)
 
 	nsc->sasl_chosen_mech = getcpy(nsc->sasl_mech);
 
-	xoauth_client_res = mh_oauth_do_xoauth(nsc->ns_userid,
-					       nsc->oauth_service,
-					       nsc->ns_snoop ? stderr : NULL);
-
-	if (xoauth_client_res == NULL) {
-	    netsec_err(errstr, "Internal error: mh_oauth_do_xoauth() "
-		       "returned NULL");
+	if (mh_oauth_do_xoauth(nsc->ns_userid, nsc->oauth_service,
+			       &xoauth_client_res, &xoauth_client_res_len,
+			       nsc->ns_snoop ? stderr : NULL) != OK) {
+	    netsec_err(errstr, "Internal error: Unable to get OAuth2 "
+	    	       "bearer token");
 	    return NOTOK;
 	}
 
-#if 0
-	rc = nsc->sasl_proto_cb(NETSEC_SASL_START, 
-#endif
+	rc = nsc->sasl_proto_cb(NETSEC_SASL_START, xoauth_client_res,
+				xoauth_client_res_len, NULL, 0, errstr);
+	free(xoauth_client_res);
+
+	if (rc != OK)
+	    return NOTOK;
+
+	/*
+	 * Okay, we need to do a NETSEC_SASL_FINISH now.  If we return
+	 * success, we indicate that with no output data.  But if we
+	 * fail, then send a blank message and get the resulting
+	 * error.
+	 */
+
+	rc = nsc->sasl_proto_cb(NETSEC_SASL_FINISH, NULL, 0, NULL, 0, errstr);
+
+	if (rc != OK) {
+	    /*
+	     * We're going to assume the error here is a JSON response;
+	     * we ignore it and send a blank message in response.  We should
+	     * then get either an +OK or -ERR
+	     */
+	    free(*errstr);
+	    nsc->sasl_proto_cb(NETSEC_SASL_WRITE, NULL, 0, NULL, 0, NULL);
+	    rc = nsc->sasl_proto_cb(NETSEC_SASL_FINISH, NULL, 0, NULL, 0,
+				    errstr);
+	    if (rc == 0) {
+		netsec_err(errstr, "Unexpected success after OAuth failure!");
+	    }
+	    return NOTOK;
+	}
+	return OK;
     }
 #endif /* OAUTH_SUPPORT */
 
@@ -1078,18 +1194,8 @@ netsec_negotiate_sasl(netsec_context *nsc, const char *mechlist, char **errstr)
 
     nsc->sasl_chosen_mech = getcpy(chosen_mech);
 
-    if (nsc->sasl_proto_cb(NETSEC_SASL_START, saslbuf, saslbuflen, &outbuf,
-			   &outbuflen, errstr) != OK)
-	return NOTOK;
-
-    if (netsec_write(nsc, outbuf, outbuflen, errstr) != OK) {
-    	free(outbuf);
-	return NOTOK;
-    }
-
-    free(outbuf);
-
-    if (netsec_flush(nsc, errstr) != OK)
+    if (nsc->sasl_proto_cb(NETSEC_SASL_START, saslbuf, saslbuflen, NULL, 0,
+			   errstr) != OK)
 	return NOTOK;
 
     /*
@@ -1104,52 +1210,28 @@ netsec_negotiate_sasl(netsec_context *nsc, const char *mechlist, char **errstr)
 
 	if (nsc->sasl_proto_cb(NETSEC_SASL_READ, NULL, 0, &outbuf, &outbuflen,
 			       errstr) != OK) {
-	    if (nsc->sasl_proto_cb(NETSEC_SASL_CANCEL, NULL, 0, &outbuf,
-				   &outbuflen, NULL) == OK) {
-		netsec_write(nsc, outbuf, outbuflen, NULL);
-		netsec_flush(nsc, NULL);
-		free(outbuf);
-	    }
+	    nsc->sasl_proto_cb(NETSEC_SASL_CANCEL, NULL, 0, NULL, 0, NULL);
 	    return NOTOK;
 	}
 
 	rc = sasl_client_step(nsc->sasl_conn, (char *) outbuf, outbuflen, NULL,
 			      (const char **) &saslbuf, &saslbuflen);
 
-	free(outbuf);
+	if (outbuf)
+	    free(outbuf);
 
 	if (rc != SASL_OK && rc != SASL_CONTINUE) {
 	    netsec_err(errstr, "SASL client negotiation failed: %s",
 		       sasl_errdetail(nsc->sasl_conn));
-	    if (nsc->sasl_proto_cb(NETSEC_SASL_CANCEL, NULL, 0, &outbuf,
-				   &outbuflen, NULL) == OK) {
-		netsec_write(nsc, outbuf, outbuflen, NULL);
-		netsec_flush(nsc, NULL);
-		free(outbuf);
-	    }
+	    nsc->sasl_proto_cb(NETSEC_SASL_CANCEL, NULL, 0, NULL, 0, NULL);
 	    return NOTOK;
 	}
 
 	if (nsc->sasl_proto_cb(NETSEC_SASL_WRITE, saslbuf, saslbuflen,
-			       &outbuf, &outbuflen, errstr) != OK) {
-	    if (nsc->sasl_proto_cb(NETSEC_SASL_CANCEL, NULL, 0, &outbuf,
-				   &outbuflen, NULL) == OK) {
-		netsec_write(nsc, outbuf, outbuflen, NULL);
-		netsec_flush(nsc, NULL);
-		free(outbuf);
-	    }
+			       NULL, 0, errstr) != OK) {
+	    nsc->sasl_proto_cb(NETSEC_SASL_CANCEL, NULL, 0, NULL, 0, NULL);
 	    return NOTOK;
 	}
-
-	if (netsec_write(nsc, outbuf, outbuflen, errstr) != OK) {
-	    free(outbuf);
-	    return NOTOK;
-	}
-
-	free(outbuf);
-
-	if (netsec_flush(nsc, errstr) != OK)
-	    return NOTOK;
     }
 
     /*
@@ -1284,7 +1366,7 @@ netsec_set_tls(netsec_context *nsc, int tls, char **errstr)
     if (tls) {
 #ifdef TLS_SUPPORT
 	SSL *ssl;
-	BIO *sbio, *ssl_bio;;
+	BIO *rbio, *wbio, *ssl_bio;;
 
 	if (! tls_initialized) {
 	    SSL_library_init();
@@ -1310,7 +1392,7 @@ netsec_set_tls(netsec_context *nsc, int tls, char **errstr)
 	    tls_initialized++;
 	}
 
-	if (nsc->ns_fd == -1) {
+	if (nsc->ns_readfd == -1 || nsc->ns_writefd == -1) {
 	    netsec_err(errstr, "Invalid file descriptor in netsec context");
 	    return NOTOK;
 	}
@@ -1350,27 +1432,28 @@ netsec_set_tls(netsec_context *nsc, int tls, char **errstr)
 	 * So writes and reads are buffered (we mostly care about writes).
 	 */
 
-	sbio = BIO_new_socket(nsc->ns_fd, BIO_NOCLOSE);
+	rbio = BIO_new_socket(nsc->ns_readfd, BIO_NOCLOSE);
 
-	if (! sbio) {
-	    netsec_err(errstr, "Unable to create a socket BIO: %s",
+	if (! rbio) {
+	    netsec_err(errstr, "Unable to create a read socket BIO: %s",
 		       ERR_error_string(ERR_get_error(), NULL));
 	    SSL_free(ssl);
 	    return NOTOK;
 	}
 
-	SSL_set_bio(ssl, sbio, sbio);
-	SSL_set_connect_state(ssl);
-
-	nsc->ssl_io = BIO_new(BIO_f_buffer());
+	wbio = BIO_new_socket(nsc->ns_writefd, BIO_NOCLOSE);
 
-	if (! nsc->ssl_io) {
-	    netsec_err(errstr, "Unable to create a buffer BIO: %s",
+	if (! wbio) {
+	    netsec_err(errstr, "Unable to create a write socket BIO: %s",
 		       ERR_error_string(ERR_get_error(), NULL));
 	    SSL_free(ssl);
+	    BIO_free(rbio);
 	    return NOTOK;
 	}
 
+	SSL_set_bio(ssl, rbio, wbio);
+	SSL_set_connect_state(ssl);
+
 	ssl_bio = BIO_new(BIO_f_ssl());
 
 	if (! ssl_bio) {
@@ -1381,7 +1464,7 @@ netsec_set_tls(netsec_context *nsc, int tls, char **errstr)
 	}
 
 	BIO_set_ssl(ssl_bio, ssl, BIO_CLOSE);
-	BIO_push(nsc->ssl_io, ssl_bio);
+	nsc->ssl_io = ssl_bio;
 
 	return OK;
     } else {
@@ -1424,7 +1507,7 @@ netsec_negotiate_tls(netsec_context *nsc, char **errstr)
 	    fprintf(stderr, "WARNING: cannot determine SSL ciphers\n");
 	} else {
 	    const SSL_CIPHER *cipher = SSL_get_current_cipher(ssl);
-	    fprintf(stderr, "TLS negotation successful: %s(%d) %s\n",
+	    fprintf(stderr, "TLS negotiation successful: %s(%d) %s\n",
 		    SSL_CIPHER_get_name(cipher),
 		    SSL_CIPHER_get_bits(cipher, NULL),
 		    SSL_CIPHER_get_version(cipher));
@@ -1433,16 +1516,6 @@ netsec_negotiate_tls(netsec_context *nsc, char **errstr)
 
     nsc->tls_active = 1;
 
-    /*
-     * At this point, TLS has been activated; we're not going to use
-     * the output buffer, so free it now to save a little bit of memory.
-     */
-
-    if (nsc->ns_outbuffer) {
-	free(nsc->ns_outbuffer);
-	nsc->ns_outbuffer = NULL;
-    }
-
     return OK;
 #else /* TLS_SUPPORT */
     netsec_err(errstr, "TLS not supported");
@@ -1455,7 +1528,7 @@ netsec_negotiate_tls(netsec_context *nsc, char **errstr)
  * Generate an (allocated) error string
  */
 
-static void
+void
 netsec_err(char **errstr, const char *fmt, ...)
 {
     va_list ap;