upstream: client: switch to sshbuf API; ok djm@

OpenBSD-Commit-ID: 60cb0356114acc7625ab85105f6f6a7cd44a8d05

8 files changed, 416 insertions, 328 deletions

diff --git a/clientloop.c b/clientloop.c
index 9a5865b2a..8da5d914e 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.c,v 1.314 2018/06/26 02:02:36 djm Exp $ */
+/* $OpenBSD: clientloop.c,v 1.315 2018/07/09 21:03:30 markus Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -91,7 +91,7 @@
 #include "ssh.h"
 #include "ssh2.h"
 #include "packet.h"
-#include "buffer.h"
+#include "sshbuf.h"
 #include "compat.h"
 #include "channels.h"
 #include "dispatch.h"
@@ -153,7 +153,7 @@ static time_t control_persist_exit_time = 0;
 volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
 static int last_was_cr;         /* Last character was a newline. */
 static int exit_status;         /* Used to store the command exit status. */
-static Buffer stderr_buffer;    /* Used for final exit message. */
+static struct sshbuf *stderr_buffer;    /* Used for final exit message. */
 static int connection_in;       /* Connection to server (input). */
 static int connection_out;      /* Connection to server (output). */
 static int need_rekeying;       /* Set to non-zero if rekeying is requested. */
@@ -188,7 +188,7 @@ TAILQ_HEAD(global_confirms, global_confirm);
 static struct global_confirms global_confirms =
     TAILQ_HEAD_INITIALIZER(global_confirms);
 
-void ssh_process_session2_setup(int, int, int, Buffer *);
+void ssh_process_session2_setup(int, int, int, struct sshbuf *);
 
 /* Restores stdin to blocking mode. */
 
@@ -493,7 +493,7 @@ client_wait_until_can_do_something(struct ssh *ssh,
         struct timeval tv, *tvp;
         int timeout_secs;
         time_t minwait_secs = 0, server_alive_time = 0, now = monotime();
-        int ret;
+        int r, ret;
 
         /* Add any selections by the channel mechanism. */
         channel_prepare_select(active_state, readsetp, writesetp, maxfdp,
@@ -546,8 +546,6 @@ client_wait_until_can_do_something(struct ssh *ssh,
 
         ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
         if (ret < 0) {
-                char buf[100];
-
                 /*
                  * We have to clear the select masks, because we return.
                  * We have to return, because the mainloop checks for the flags
@@ -559,8 +557,9 @@ client_wait_until_can_do_something(struct ssh *ssh,
                 if (errno == EINTR)
                         return;
                 /* Note: we might still have data in the buffers. */
-                snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
-                buffer_append(&stderr_buffer, buf, strlen(buf));
+                if ((r = sshbuf_putf(stderr_buffer,
+                    "select: %s\r\n", strerror(errno))) != 0)
+                        fatal("%s: buffer error: %s", __func__, ssh_err(r));
                 quit_pending = 1;
         } else if (ret == 0) {
                 /*
@@ -574,15 +573,15 @@ client_wait_until_can_do_something(struct ssh *ssh,
 }
 
 static void
-client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
+client_suspend_self(struct sshbuf *bin, struct sshbuf *bout, struct sshbuf *berr)
 {
         /* Flush stdout and stderr buffers. */
-        if (buffer_len(bout) > 0)
-                atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
-                    buffer_len(bout));
-        if (buffer_len(berr) > 0)
-                atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
-                    buffer_len(berr));
+        if (sshbuf_len(bout) > 0)
+                atomicio(vwrite, fileno(stdout), sshbuf_mutable_ptr(bout),
+                    sshbuf_len(bout));
+        if (sshbuf_len(berr) > 0)
+                atomicio(vwrite, fileno(stderr), sshbuf_mutable_ptr(berr),
+                    sshbuf_len(berr));
 
         leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
 
@@ -602,8 +601,8 @@ client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
 static void
 client_process_net_input(fd_set *readset)
 {
-        int len;
         char buf[SSH_IOBUFSZ];
+        int r, len;
 
         /*
          * Read input from the server, and add any such data to the buffer of
@@ -617,10 +616,11 @@ client_process_net_input(fd_set *readset)
                          * Received EOF.  The remote host has closed the
                          * connection.
                          */
-                        snprintf(buf, sizeof buf,
+                        if ((r = sshbuf_putf(stderr_buffer,
                             "Connection to %.300s closed by remote host.\r\n",
-                            host);
-                        buffer_append(&stderr_buffer, buf, strlen(buf));
+                            host)) != 0)
+                                fatal("%s: buffer error: %s",
+                                    __func__, ssh_err(r));
                         quit_pending = 1;
                         return;
                 }
@@ -637,10 +637,11 @@ client_process_net_input(fd_set *readset)
                          * An error has encountered.  Perhaps there is a
                          * network problem.
                          */
-                        snprintf(buf, sizeof buf,
+                        if ((r = sshbuf_putf(stderr_buffer,
                             "Read from remote host %.300s: %.100s\r\n",
-                            host, strerror(errno));
-                        buffer_append(&stderr_buffer, buf, strlen(buf));
+                            host, strerror(errno))) != 0)
+                                fatal("%s: buffer error: %s",
+                                    __func__, ssh_err(r));
                         quit_pending = 1;
                         return;
                 }
@@ -653,7 +654,7 @@ client_status_confirm(struct ssh *ssh, int type, Channel *c, void *ctx)
 {
         struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
         char errmsg[256];
-        int tochan;
+        int r, tochan;
 
         /*
          * If a TTY was explicitly requested, then a failure to allocate
@@ -688,7 +689,10 @@ client_status_confirm(struct ssh *ssh, int type, Channel *c, void *ctx)
                  * their stderr.
                  */
                 if (tochan) {
-                        buffer_append(c->extended, errmsg, strlen(errmsg));
+                        if ((r = sshbuf_put(c->extended, errmsg,
+                            strlen(errmsg))) != 0)
+                                fatal("%s: buffer error %s", __func__,
+                                    ssh_err(r));
                 } else
                         error("%s", errmsg);
                 if (cr->action == CONFIRM_TTY) {
@@ -892,14 +896,15 @@ static struct escape_help_text esc_txt[] = {
 };
 
 static void
-print_escape_help(Buffer *b, int escape_char, int mux_client, int using_stderr)
+print_escape_help(struct sshbuf *b, int escape_char, int mux_client,
+    int using_stderr)
 {
         unsigned int i, suppress_flags;
-        char string[1024];
+        int r;
 
-        snprintf(string, sizeof string, "%c?\r\n"
-            "Supported escape sequences:\r\n", escape_char);
-        buffer_append(b, string, strlen(string));
+        if ((r = sshbuf_putf(b,
+            "%c?\r\nSupported escape sequences:\r\n", escape_char)) != 0)
+                fatal("%s: buffer error: %s", __func__, ssh_err(r));
 
         suppress_flags =
             (mux_client ? SUPPRESS_MUXCLIENT : 0) |
@@ -909,16 +914,16 @@ print_escape_help(Buffer *b, int escape_char, int mux_client, int using_stderr)
         for (i = 0; i < sizeof(esc_txt)/sizeof(esc_txt[0]); i++) {
                 if (esc_txt[i].flags & suppress_flags)
                         continue;
-                snprintf(string, sizeof string, " %c%-3s - %s\r\n",
-                    escape_char, esc_txt[i].cmd, esc_txt[i].text);
-                buffer_append(b, string, strlen(string));
+                if ((r = sshbuf_putf(b, " %c%-3s - %s\r\n",
+                    escape_char, esc_txt[i].cmd, esc_txt[i].text)) != 0)
+                        fatal("%s: buffer error: %s", __func__, ssh_err(r));
         }
 
-        snprintf(string, sizeof string,
+        if ((r = sshbuf_putf(b,
             " %c%c   - send the escape character by typing it twice\r\n"
             "(Note that escapes are only recognized immediately after "
-            "newline.)\r\n", escape_char, escape_char);
-        buffer_append(b, string, strlen(string));
+            "newline.)\r\n", escape_char, escape_char)) != 0)
+                fatal("%s: buffer error: %s", __func__, ssh_err(r));
 }
 
 /*
@@ -926,12 +931,11 @@ print_escape_help(Buffer *b, int escape_char, int mux_client, int using_stderr)
  */
 static int
 process_escapes(struct ssh *ssh, Channel *c,
-    Buffer *bin, Buffer *bout, Buffer *berr,
+    struct sshbuf *bin, struct sshbuf *bout, struct sshbuf *berr,
     char *buf, int len)
 {
-        char string[1024];
         pid_t pid;
-        int bytes = 0;
+        int r, bytes = 0;
         u_int i;
         u_char ch;
         char *s;
@@ -957,10 +961,10 @@ process_escapes(struct ssh *ssh, Channel *c,
                         switch (ch) {
                         case '.':
                                 /* Terminate the connection. */
-                                snprintf(string, sizeof string, "%c.\r\n",
-                                    efc->escape_char);
-                                buffer_append(berr, string, strlen(string));
-
+                                if ((r = sshbuf_putf(berr, "%c.\r\n",
+                                    efc->escape_char)) != 0)
+                                        fatal("%s: buffer error: %s",
+                                            __func__, ssh_err(r));
                                 if (c && c->ctl_chan != -1) {
                                         chan_read_failed(ssh, c);
                                         chan_write_failed(ssh, c);
@@ -969,7 +973,7 @@ process_escapes(struct ssh *ssh, Channel *c,
                                                     c->self, NULL);
                                         }
                                         c->type = SSH_CHANNEL_ABANDONED;
-                                        buffer_clear(c->input);
+                                        sshbuf_reset(c->input);
                                         chan_ibuf_empty(ssh, c);
                                         return 0;
                                 } else
@@ -985,18 +989,20 @@ process_escapes(struct ssh *ssh, Channel *c,
                                                 snprintf(b, sizeof b, "^Z");
                                         else
                                                 snprintf(b, sizeof b, "%c", ch);
-                                        snprintf(string, sizeof string,
+                                        if ((r = sshbuf_putf(berr,
                                             "%c%s escape not available to "
                                             "multiplexed sessions\r\n",
-                                            efc->escape_char, b);
-                                        buffer_append(berr, string,
-                                            strlen(string));
+                                            efc->escape_char, b)) != 0)
+                                                fatal("%s: buffer error: %s",
+                                                    __func__, ssh_err(r));
                                         continue;
                                 }
                                 /* Suspend the program. Inform the user */
-                                snprintf(string, sizeof string,
-                                    "%c^Z [suspend ssh]\r\n", efc->escape_char);
-                                buffer_append(berr, string, strlen(string));
+                                if ((r = sshbuf_putf(berr,
+                                    "%c^Z [suspend ssh]\r\n",
+                                    efc->escape_char)) != 0)
+                                        fatal("%s: buffer error: %s",
+                                            __func__, ssh_err(r));
 
                                 /* Restore terminal modes and suspend. */
                                 client_suspend_self(bin, bout, berr);
@@ -1005,12 +1011,15 @@ process_escapes(struct ssh *ssh, Channel *c,
                                 continue;
 
                         case 'B':
-                                snprintf(string, sizeof string,
-                                    "%cB\r\n", efc->escape_char);
-                                buffer_append(berr, string, strlen(string));
+                                if ((r = sshbuf_putf(berr,
+                                    "%cB\r\n", efc->escape_char)) != 0)
+                                        fatal("%s: buffer error: %s",
+                                            __func__, ssh_err(r));
                                 channel_request_start(ssh, c->self, "break", 0);
-                                packet_put_int(1000);
-                                packet_send();
+                                if ((r = sshpkt_put_u32(ssh, 1000)) != 0 ||
+                                    (r = sshpkt_send(ssh)) != 0)
+                                        fatal("%s: %s", __func__,
+                                            ssh_err(r));
                                 continue;
 
                         case 'R':
@@ -1027,11 +1036,11 @@ process_escapes(struct ssh *ssh, Channel *c,
                                 if (c && c->ctl_chan != -1)
                                         goto noescape;
                                 if (!log_is_on_stderr()) {
-                                        snprintf(string, sizeof string,
+                                        if ((r = sshbuf_putf(berr,
                                             "%c%c [Logging to syslog]\r\n",
-                                             efc->escape_char, ch);
-                                        buffer_append(berr, string,
-                                            strlen(string));
+                                            efc->escape_char, ch)) != 0)
+                                                fatal("%s: buffer error: %s",
+                                                    __func__, ssh_err(r));
                                         continue;
                                 }
                                 if (ch == 'V' && options.log_level >
@@ -1040,11 +1049,12 @@ process_escapes(struct ssh *ssh, Channel *c,
                                 if (ch == 'v' && options.log_level <
                                     SYSLOG_LEVEL_DEBUG3)
                                         log_change_level(++options.log_level);
-                                snprintf(string, sizeof string,
+                                if ((r = sshbuf_putf(berr,
                                     "%c%c [LogLevel %s]\r\n",
                                     efc->escape_char, ch,
-                                    log_level_name(options.log_level));
-                                buffer_append(berr, string, strlen(string));
+                                    log_level_name(options.log_level))) != 0)
+                                        fatal("%s: buffer error: %s",
+                                            __func__, ssh_err(r));
                                 continue;
 
                         case '&':
@@ -1062,9 +1072,11 @@ process_escapes(struct ssh *ssh, Channel *c,
                                 /* Stop listening for new connections. */
                                 channel_stop_listening(ssh);
 
-                                snprintf(string, sizeof string,
-                                    "%c& [backgrounded]\n", efc->escape_char);
-                                buffer_append(berr, string, strlen(string));
+                                if ((r = sshbuf_putf(berr,
+                                    "%c& [backgrounded]\n", efc->escape_char))
+                                     != 0)
+                                        fatal("%s: buffer error: %s",
+                                            __func__, ssh_err(r));
 
                                 /* Fork into background. */
                                 pid = fork();
@@ -1077,8 +1089,10 @@ process_escapes(struct ssh *ssh, Channel *c,
                                         exit(0);
                                 }
                                 /* The child continues serving connections. */
-                                buffer_append(bin, "\004", 1);
                                 /* fake EOF on stdin */
+                                if ((r = sshbuf_put_u8(bin, 4)) != 0)
+                                        fatal("%s: buffer error: %s",
+                                            __func__, ssh_err(r));
                                 return -1;
                         case '?':
                                 print_escape_help(berr, efc->escape_char,
@@ -1087,11 +1101,14 @@ process_escapes(struct ssh *ssh, Channel *c,
                                 continue;
 
                         case '#':
-                                snprintf(string, sizeof string, "%c#\r\n",
-                                    efc->escape_char);
-                                buffer_append(berr, string, strlen(string));
+                                if ((r = sshbuf_putf(berr, "%c#\r\n",
+                                    efc->escape_char)) != 0)
+                                        fatal("%s: buffer error: %s",
+                                            __func__, ssh_err(r));
                                 s = channel_open_message(ssh);
-                                buffer_append(berr, s, strlen(s));
+                                if ((r = sshbuf_put(berr, s, strlen(s))) != 0)
+                                        fatal("%s: buffer error: %s",
+                                            __func__, ssh_err(r));
                                 free(s);
                                 continue;
 
@@ -1103,7 +1120,10 @@ process_escapes(struct ssh *ssh, Channel *c,
 
                         default:
                                 if (ch != efc->escape_char) {
-                                        buffer_put_char(bin, efc->escape_char);
+                                        if ((r = sshbuf_put_u8(bin,
+                                            efc->escape_char)) != 0)
+                                                fatal("%s: buffer error: %s",
+                                                    __func__, ssh_err(r));
                                         bytes++;
                                 }
                                 /* Escaped characters fall through here */
@@ -1129,7 +1149,8 @@ process_escapes(struct ssh *ssh, Channel *c,
                  * and append it to the buffer.
                  */
                 last_was_cr = (ch == '\r' || ch == '\n');
-                buffer_put_char(bin, ch);
+                if ((r = sshbuf_put_u8(bin, ch)) != 0)
+                        fatal("%s: buffer error: %s", __func__, ssh_err(r));
                 bytes++;
         }
         return bytes;
@@ -1253,8 +1274,9 @@ client_loop(struct ssh *ssh, int have_pty, int escape_char_arg,
 
         quit_pending = 0;
 
-        /* Initialize buffers. */
-        buffer_init(&stderr_buffer);
+        /* Initialize buffer. */
+        if ((stderr_buffer = sshbuf_new()) == NULL)
+                fatal("%s: sshbuf_new failed", __func__);
 
         client_init_dispatch();
 
@@ -1411,24 +1433,25 @@ client_loop(struct ssh *ssh, int have_pty, int escape_char_arg,
          * that the connection has been closed.
          */
         if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
-                snprintf(buf, sizeof buf,
-                    "Connection to %.64s closed.\r\n", host);
-                buffer_append(&stderr_buffer, buf, strlen(buf));
+                if ((r = sshbuf_putf(stderr_buffer,
+                    "Connection to %.64s closed.\r\n", host)) != 0)
+                        fatal("%s: buffer error: %s", __func__, ssh_err(r));
         }
 
         /* Output any buffered data for stderr. */
-        if (buffer_len(&stderr_buffer) > 0) {
+        if (sshbuf_len(stderr_buffer) > 0) {
                 len = atomicio(vwrite, fileno(stderr),
-                    buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
-                if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
+                    (u_char *)sshbuf_ptr(stderr_buffer),
+                    sshbuf_len(stderr_buffer));
+                if (len < 0 || (u_int)len != sshbuf_len(stderr_buffer))
                         error("Write failed flushing stderr buffer.");
-                else
-                        buffer_consume(&stderr_buffer, len);
+                else if ((r = sshbuf_consume(stderr_buffer, len)) != 0)
+                        fatal("%s: buffer error: %s", __func__, ssh_err(r));
         }
 
         /* Clear and free any buffers. */
         explicit_bzero(buf, sizeof(buf));
-        buffer_free(&stderr_buffer);
+        sshbuf_free(stderr_buffer);
 
         /* Report bytes transferred, and transfer rates. */
         total_time = monotime_double() - start_time;
@@ -2156,7 +2179,8 @@ client_input_global_request(int type, u_int32_t seq, struct ssh *ssh)
 
 void
 client_session2_setup(struct ssh *ssh, int id, int want_tty, int want_subsystem,
-    const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
+    const char *term, struct termios *tiop, int in_fd, struct sshbuf *cmd,
+    char **env)
 {
         int i, j, matched, len;
         char *name, *val;
@@ -2242,23 +2266,23 @@ client_session2_setup(struct ssh *ssh, int id, int want_tty, int want_subsystem,
                 free(name);
         }
 
-        len = buffer_len(cmd);
+        len = sshbuf_len(cmd);
         if (len > 0) {
                 if (len > 900)
                         len = 900;
                 if (want_subsystem) {
                         debug("Sending subsystem: %.*s",
-                            len, (u_char*)buffer_ptr(cmd));
+                            len, (const u_char*)sshbuf_ptr(cmd));
                         channel_request_start(ssh, id, "subsystem", 1);
                         client_expect_confirm(ssh, id, "subsystem",
                             CONFIRM_CLOSE);
                 } else {
                         debug("Sending command: %.*s",
-                            len, (u_char*)buffer_ptr(cmd));
+                            len, (const u_char*)sshbuf_ptr(cmd));
                         channel_request_start(ssh, id, "exec", 1);
                         client_expect_confirm(ssh, id, "exec", CONFIRM_CLOSE);
                 }
-                packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
+                packet_put_string(sshbuf_ptr(cmd), sshbuf_len(cmd));
                 packet_send();
         } else {
                 channel_request_start(ssh, id, "shell", 1);
diff --git a/clientloop.h b/clientloop.h
index 8d1f0bff6..bf79c87bf 100644
--- a/clientloop.h
+++ b/clientloop.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.h,v 1.35 2017/10/23 05:08:00 djm Exp $ */
+/* $OpenBSD: clientloop.h,v 1.36 2018/07/09 21:03:30 markus Exp $ */
 
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -45,7 +45,7 @@ int	 client_x11_get_proto(struct ssh *, const char *, const char *,
             u_int, u_int, char **, char **);
 void     client_global_request_reply_fwd(int, u_int32_t, void *);
 void     client_session2_setup(struct ssh *, int, int, int,
-            const char *, struct termios *, int, Buffer *, char **);
+            const char *, struct termios *, int, struct sshbuf *, char **);
 char     *client_request_tun_fwd(struct ssh *, int, int, int);
 void     client_stop_mux(void);
 
diff --git a/compat.c b/compat.c
index d8fd6eaf8..d0afe9084 100644
--- a/compat.c
+++ b/compat.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: compat.c,v 1.110 2018/07/04 13:49:31 djm Exp $ */
+/* $OpenBSD: compat.c,v 1.111 2018/07/09 21:03:30 markus Exp $ */
 /*
  * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl.  All rights reserved.
  *
@@ -32,7 +32,6 @@
 #include <stdarg.h>
 
 #include "xmalloc.h"
-#include "buffer.h"
 #include "packet.h"
 #include "compat.h"
 #include "log.h"
diff --git a/mux.c b/mux.c
index 8433cd8e5..474d610a3 100644
--- a/mux.c
+++ b/mux.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: mux.c,v 1.71 2018/06/09 03:01:12 djm Exp $ */
+/* $OpenBSD: mux.c,v 1.72 2018/07/09 21:03:30 markus Exp $ */
 /*
  * Copyright (c) 2002-2008 Damien Miller <djm@openbsd.org>
  *
@@ -87,7 +87,7 @@ extern Options options;
 extern int stdin_null_flag;
 extern char *host;
 extern int subsystem_flag;
-extern Buffer command;
+extern struct sshbuf *command;
 extern volatile sig_atomic_t quit_pending;
 
 /* Context for session open confirmation callback */
@@ -1887,7 +1887,7 @@ mux_client_request_session(int fd)
         buffer_put_int(&m, options.escape_char == SSH_ESCAPECHAR_NONE ?
             0xffffffff : (u_int)options.escape_char);
         buffer_put_cstring(&m, term == NULL ? "" : term);
-        buffer_put_string(&m, buffer_ptr(&command), buffer_len(&command));
+        buffer_put_string(&m, buffer_ptr(command), buffer_len(command));
 
         /* Pass environment */
         if (options.num_send_env > 0 && environ != NULL) {
diff --git a/packet.c b/packet.c
index 4d91792e0..cacb6eebe 100644
--- a/packet.c
+++ b/packet.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: packet.c,v 1.275 2018/07/09 13:37:10 sf Exp $ */
+/* $OpenBSD: packet.c,v 1.276 2018/07/09 21:03:30 markus Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -63,9 +63,6 @@
 
 #include <zlib.h>
 
-#include "buffer.h"     /* typedefs XXX */
-#include "key.h"        /* typedefs XXX */
-
 #include "xmalloc.h"
 #include "crc32.h"
 #include "compat.h"
diff --git a/ssh.c b/ssh.c
index fe3e1a83a..914167789 100644
--- a/ssh.c
+++ b/ssh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh.c,v 1.481 2018/06/08 03:35:36 djm Exp $ */
+/* $OpenBSD: ssh.c,v 1.482 2018/07/09 21:03:30 markus Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -87,7 +87,7 @@
 #include "cipher.h"
 #include "digest.h"
 #include "packet.h"
-#include "buffer.h"
+#include "sshbuf.h"
 #include "channels.h"
 #include "key.h"
 #include "authfd.h"
@@ -183,7 +183,7 @@ uid_t original_real_uid;
 uid_t original_effective_uid;
 
 /* command to be executed */
-Buffer command;
+struct sshbuf *command;
 
 /* Should we execute a command or invoke a subsystem? */
 int subsystem_flag = 0;
@@ -1042,7 +1042,8 @@ main(int ac, char **av)
 #endif
 
         /* Initialize the command to execute on remote host. */
-        buffer_init(&command);
+        if ((command = sshbuf_new()) == NULL)
+                fatal("sshbuf_new failed");
 
         /*
          * Save the command to execute on the remote host in a buffer. There
@@ -1059,9 +1060,10 @@ main(int ac, char **av)
         } else {
                 /* A command has been specified.  Store it into the buffer. */
                 for (i = 0; i < ac; i++) {
-                        if (i)
-                                buffer_append(&command, " ", 1);
-                        buffer_append(&command, av[i], strlen(av[i]));
+                        if ((r = sshbuf_putf(command, "%s%s",
+                            i ? " " : "", av[i])) != 0)
+                                fatal("%s: buffer error: %s",
+                                    __func__, ssh_err(r));
                 }
         }
 
@@ -1234,11 +1236,11 @@ main(int ac, char **av)
                 options.use_privileged_port = 0;
 #endif
 
-        if (buffer_len(&command) != 0 && options.remote_command != NULL)
+        if (sshbuf_len(command) != 0 && options.remote_command != NULL)
                 fatal("Cannot execute command-line and remote command.");
 
         /* Cannot fork to background if no command. */
-        if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
+        if (fork_after_authentication_flag && sshbuf_len(command) == 0 &&
             options.remote_command == NULL && !no_shell_flag)
                 fatal("Cannot fork into background without a command "
                     "to execute.");
@@ -1251,7 +1253,7 @@ main(int ac, char **av)
                 tty_flag = 1;
 
         /* Allocate a tty by default if no command specified. */
-        if (buffer_len(&command) == 0 && options.remote_command == NULL)
+        if (sshbuf_len(command) == 0 && options.remote_command == NULL)
                 tty_flag = options.request_tty != REQUEST_TTY_NO;
 
         /* Force no tty */
@@ -1313,8 +1315,9 @@ main(int ac, char **av)
                     (char *)NULL);
                 debug3("expanded RemoteCommand: %s", options.remote_command);
                 free(cp);
-                buffer_append(&command, options.remote_command,
-                    strlen(options.remote_command));
+                if ((r = sshbuf_put(command, options.remote_command,
+                    strlen(options.remote_command))) != 0)
+                        fatal("%s: buffer error: %s", __func__, ssh_err(r));
         }
 
         if (options.control_path != NULL) {
@@ -1846,7 +1849,7 @@ ssh_session2_setup(struct ssh *ssh, int id, int success, void *arg)
             options.ip_qos_interactive, options.ip_qos_bulk);
 
         client_session2_setup(ssh, id, tty_flag, subsystem_flag, getenv("TERM"),
-            NULL, fileno(stdin), &command, environ);
+            NULL, fileno(stdin), command, environ);
 }
 
 /* open new channel for a session */
diff --git a/sshconnect.c b/sshconnect.c
index 32f9c8b3a..afe294660 100644
--- a/sshconnect.c
+++ b/sshconnect.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect.c,v 1.298 2018/04/10 00:10:49 djm Exp $ */
+/* $OpenBSD: sshconnect.c,v 1.299 2018/07/09 21:03:30 markus Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -52,7 +52,7 @@
 #include "key.h"
 #include "hostfile.h"
 #include "ssh.h"
-#include "buffer.h"
+#include "sshbuf.h"
 #include "packet.h"
 #include "uidswap.h"
 #include "compat.h"
@@ -771,7 +771,7 @@ check_host_cert(const char *host, const struct sshkey *host_key)
                 error("%s", reason);
                 return 0;
         }
-        if (buffer_len(host_key->cert->critical) != 0) {
+        if (sshbuf_len(host_key->cert->critical) != 0) {
                 error("Certificate for %s contains unsupported "
                     "critical options(s)", host);
                 return 0;
diff --git a/sshconnect2.c b/sshconnect2.c
index 4bc0a7034..2194e3a8d 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect2.c,v 1.277 2018/07/09 13:37:10 sf Exp $ */
+/* $OpenBSD: sshconnect2.c,v 1.278 2018/07/09 21:03:30 markus Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2008 Damien Miller.  All rights reserved.
@@ -49,11 +49,11 @@
 #include "xmalloc.h"
 #include "ssh.h"
 #include "ssh2.h"
-#include "buffer.h"
+#include "sshbuf.h"
 #include "packet.h"
 #include "compat.h"
 #include "cipher.h"
-#include "key.h"
+#include "sshkey.h"
 #include "kex.h"
 #include "myproposal.h"
 #include "sshconnect.h"
@@ -232,10 +232,11 @@ ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
 
 #ifdef DEBUG_KEXDH
         /* send 1st encrypted/maced/compressed message */
-        packet_start(SSH2_MSG_IGNORE);
-        packet_put_cstring("markus");
-        packet_send();
-        packet_write_wait();
+        if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
+            (r = sshpkt_send(ssh)) != 0)
+                fatal("%s: %s", __func__, ssh_err(r));
+        ssh_packet_write_wait(ssh);
 #endif
 }
 
@@ -457,6 +458,8 @@ input_userauth_ext_info(int type, u_int32_t seqnr, struct ssh *ssh)
 void
 userauth(Authctxt *authctxt, char *authlist)
 {
+        struct ssh *ssh = active_state; /* XXX */
+
         if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
                 authctxt->method->cleanup(authctxt);
 
@@ -476,7 +479,7 @@ userauth(Authctxt *authctxt, char *authlist)
                 authctxt->method = method;
 
                 /* reset the per method handler */
-                dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
+                ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
                     SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
 
                 /* and try new method */
@@ -553,14 +556,16 @@ input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
 {
         Authctxt *authctxt = ssh->authctxt;
         char *authlist = NULL;
-        int partial;
+        u_char partial;
+        int r;
 
         if (authctxt == NULL)
                 fatal("input_userauth_failure: no authentication context");
 
-        authlist = packet_get_string(NULL);
-        partial = packet_get_char();
-        packet_check_eom();
+        if ((r = sshpkt_get_cstring(ssh, &authlist, NULL)) != 0 ||
+            (r = sshpkt_get_u8(ssh, &partial)) != 0 ||
+            (r = sshpkt_get_end(ssh)) != 0)
+                goto out;
 
         if (partial != 0) {
                 verbose("Authenticated with partial success.");
@@ -570,6 +575,9 @@ input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
         debug("Authentications that can continue: %s", authlist);
 
         userauth(authctxt, authlist);
+        authlist = NULL;
+ out:
+        free(authlist);
         return 0;
 }
 
@@ -581,25 +589,27 @@ input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
         struct sshkey *key = NULL;
         Identity *id = NULL;
         int pktype, sent = 0;
-        u_int alen, blen;
-        char *pkalg, *fp;
-        u_char *pkblob;
+        size_t blen;
+        char *pkalg = NULL, *fp;
+        u_char *pkblob = NULL;
+        int r;
 
         if (authctxt == NULL)
                 fatal("input_userauth_pk_ok: no authentication context");
 
-        pkalg = packet_get_string(&alen);
-        pkblob = packet_get_string(&blen);
-        packet_check_eom();
+        if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
+            (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
+            (r = sshpkt_get_end(ssh)) != 0)
+                goto done;
 
-        debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
+        debug("Server accepts key: pkalg %s blen %zu", pkalg, blen);
 
-        if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
+        if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
                 debug("unknown pkalg %s", pkalg);
                 goto done;
         }
-        if ((key = key_from_blob(pkblob, blen)) == NULL) {
-                debug("no key from blob. pkalg %s", pkalg);
+        if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
+                debug("no key from blob. pkalg %s: %s", pkalg, ssh_err(r));
                 goto done;
         }
         if (key->type != pktype) {
@@ -620,31 +630,33 @@ input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
          * duplicate keys
          */
         TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
-                if (key_equal(key, id->key)) {
+                if (sshkey_equal(key, id->key)) {
                         sent = sign_and_send_pubkey(ssh, authctxt, id);
                         break;
                 }
         }
-done:
-        key_free(key);
+        r = 0;
+ done:
+        sshkey_free(key);
         free(pkalg);
         free(pkblob);
 
         /* try another method if we did not send a packet */
-        if (sent == 0)
+        if (r == 0 && sent == 0)
                 userauth(authctxt, NULL);
-        return 0;
+        return r;
 }
 
 #ifdef GSSAPI
 int
 userauth_gssapi(Authctxt *authctxt)
 {
+        struct ssh *ssh = active_state; /* XXX */
         Gssctxt *gssctxt = NULL;
         static gss_OID_set gss_supported = NULL;
         static u_int mech = 0;
         OM_uint32 min;
-        int ok = 0;
+        int r, ok = 0;
 
         /* Try one GSSAPI method at a time, rather than sending them all at
          * once. */
@@ -669,25 +681,26 @@ userauth_gssapi(Authctxt *authctxt)
 
         authctxt->methoddata=(void *)gssctxt;
 
-        packet_start(SSH2_MSG_USERAUTH_REQUEST);
-        packet_put_cstring(authctxt->server_user);
-        packet_put_cstring(authctxt->service);
-        packet_put_cstring(authctxt->method->name);
-
-        packet_put_int(1);
-
-        packet_put_int((gss_supported->elements[mech].length) + 2);
-        packet_put_char(SSH_GSS_OIDTYPE);
-        packet_put_char(gss_supported->elements[mech].length);
-        packet_put_raw(gss_supported->elements[mech].elements,
-            gss_supported->elements[mech].length);
-
-        packet_send();
+        if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
+            (r = sshpkt_put_u32(ssh, 1)) != 0 ||
+            (r = sshpkt_put_u32(ssh,
+            (gss_supported->elements[mech].length) + 2)) != 0 ||
+            (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
+            (r = sshpkt_put_u8(ssh,
+            gss_supported->elements[mech].length)) != 0 ||
+            (r = sshpkt_put(ssh,
+            gss_supported->elements[mech].elements,
+            gss_supported->elements[mech].length)) != 0 ||
+            (r = sshpkt_send(ssh)) != 0)
+                fatal("%s: %s", __func__, ssh_err(r));
 
-        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
-        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
-        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
-        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
+        ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
+        ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
+        ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
+        ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
 
         mech++; /* Move along to next candidate */
 
@@ -703,44 +716,56 @@ process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
         gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
         gss_buffer_desc gssbuf;
         OM_uint32 status, ms, flags;
-        Buffer b;
+        int r;
 
         status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
             recv_tok, &send_tok, &flags);
 
         if (send_tok.length > 0) {
-                if (GSS_ERROR(status))
-                        packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
-                else
-                        packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
+                u_char type = GSS_ERROR(status) ?
+                    SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
+                    SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
+
+                if ((r = sshpkt_start(ssh, type)) != 0 ||
+                    (r = sshpkt_put_string(ssh, send_tok.value,
+                    send_tok.length)) != 0 ||
+                    (r = sshpkt_send(ssh)) != 0)
+                        fatal("%s: %s", __func__, ssh_err(r));
 
-                packet_put_string(send_tok.value, send_tok.length);
-                packet_send();
                 gss_release_buffer(&ms, &send_tok);
         }
 
         if (status == GSS_S_COMPLETE) {
                 /* send either complete or MIC, depending on mechanism */
                 if (!(flags & GSS_C_INTEG_FLAG)) {
-                        packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
-                        packet_send();
+                        if ((r = sshpkt_start(ssh,
+                            SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
+                            (r = sshpkt_send(ssh)) != 0)
+                                fatal("%s: %s", __func__, ssh_err(r));
                 } else {
-                        ssh_gssapi_buildmic(&b, authctxt->server_user,
+                        struct sshbuf *b;
+
+                        if ((b = sshbuf_new()) == NULL)
+                                fatal("%s: sshbuf_new failed", __func__);
+                        ssh_gssapi_buildmic(b, authctxt->server_user,
                             authctxt->service, "gssapi-with-mic");
 
-                        gssbuf.value = buffer_ptr(&b);
-                        gssbuf.length = buffer_len(&b);
+                        if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
+                                fatal("%s: sshbuf_mutable_ptr failed", __func__);
+                        gssbuf.length = sshbuf_len(b);
 
                         status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
 
                         if (!GSS_ERROR(status)) {
-                                packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
-                                packet_put_string(mic.value, mic.length);
-
-                                packet_send();
+                                if ((r = sshpkt_start(ssh,
+                                    SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
+                                    (r = sshpkt_put_string(ssh, mic.value,
+                                    mic.length)) != 0 ||
+                                    (r = sshpkt_send(ssh)) != 0)
+                                        fatal("%s: %s", __func__, ssh_err(r));
                         }
 
-                        buffer_free(&b);
+                        sshbuf_free(b);
                         gss_release_buffer(&ms, &mic);
                 }
         }
@@ -754,39 +779,43 @@ input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
 {
         Authctxt *authctxt = ssh->authctxt;
         Gssctxt *gssctxt;
-        int oidlen;
-        char *oidv;
+        size_t oidlen;
+        u_char *oidv = NULL;
+        int r;
 
         if (authctxt == NULL)
                 fatal("input_gssapi_response: no authentication context");
         gssctxt = authctxt->methoddata;
 
         /* Setup our OID */
-        oidv = packet_get_string(&oidlen);
+        if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
+                goto done;
 
         if (oidlen <= 2 ||
             oidv[0] != SSH_GSS_OIDTYPE ||
             oidv[1] != oidlen - 2) {
-                free(oidv);
                 debug("Badly encoded mechanism OID received");
                 userauth(authctxt, NULL);
-                return 0;
+                goto ok;
         }
 
         if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
                 fatal("Server returned different OID than expected");
 
-        packet_check_eom();
-
-        free(oidv);
+        if ((r = sshpkt_get_end(ssh)) != 0)
+                goto done;
 
         if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
                 /* Start again with next method on list */
                 debug("Trying to start again");
                 userauth(authctxt, NULL);
-                return 0;
+                goto ok;
         }
-        return 0;
+ ok:
+        r = 0;
+ done:
+        free(oidv);
+        return r;
 }
 
 /* ARGSUSED */
@@ -795,27 +824,31 @@ input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
 {
         Authctxt *authctxt = ssh->authctxt;
         gss_buffer_desc recv_tok;
+        u_char *p = NULL;
+        size_t len;
         OM_uint32 status;
-        u_int slen;
+        int r;
 
         if (authctxt == NULL)
                 fatal("input_gssapi_response: no authentication context");
 
-        recv_tok.value = packet_get_string(&slen);
-        recv_tok.length = slen; /* safe typecast */
-
-        packet_check_eom();
+        if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
+            (r = sshpkt_get_end(ssh)) != 0)
+                goto out;
 
+        recv_tok.value = p;
+        recv_tok.length = len;
         status = process_gssapi_token(ssh, &recv_tok);
 
-        free(recv_tok.value);
-
+        /* Start again with the next method in the list */
         if (GSS_ERROR(status)) {
-                /* Start again with the next method in the list */
                 userauth(authctxt, NULL);
-                return 0;
+                /* ok */
         }
-        return 0;
+        r = 0;
+ out:
+        free(p);
+        return r;
 }
 
 /* ARGSUSED */
@@ -827,22 +860,26 @@ input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
         gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
         gss_buffer_desc recv_tok;
         OM_uint32 ms;
-        u_int len;
+        u_char *p = NULL;
+        size_t len;
+        int r;
 
         if (authctxt == NULL)
                 fatal("input_gssapi_response: no authentication context");
         gssctxt = authctxt->methoddata;
 
-        recv_tok.value = packet_get_string(&len);
-        recv_tok.length = len;
-
-        packet_check_eom();
+        if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
+            (r = sshpkt_get_end(ssh)) != 0) {
+                free(p);
+                return r;
+        }
 
         /* Stick it into GSSAPI and see what it says */
+        recv_tok.value = p;
+        recv_tok.length = len;
         (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
             &recv_tok, &send_tok, NULL);
-
-        free(recv_tok.value);
+        free(p);
         gss_release_buffer(&ms, &send_tok);
 
         /* Server will be returning a failed packet after this one */
@@ -853,43 +890,50 @@ input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
 int
 input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
 {
-        char *msg;
-        char *lang;
-
-        /* maj */(void)packet_get_int();
-        /* min */(void)packet_get_int();
-        msg=packet_get_string(NULL);
-        lang=packet_get_string(NULL);
-
-        packet_check_eom();
+        char *msg = NULL;
+        char *lang = NULL;
+        int r;
 
+        if ((r = sshpkt_get_u32(ssh, NULL)) != 0 ||     /* maj */
+            (r = sshpkt_get_u32(ssh, NULL)) != 0 ||     /* min */
+            (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
+            (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
+                goto out;
+        r = sshpkt_get_end(ssh);
         debug("Server GSSAPI Error:\n%s", msg);
+ out:
         free(msg);
         free(lang);
-        return 0;
+        return r;
 }
 #endif /* GSSAPI */
 
 int
 userauth_none(Authctxt *authctxt)
 {
+        struct ssh *ssh = active_state; /* XXX */
+        int r;
+
         /* initial userauth request */
-        packet_start(SSH2_MSG_USERAUTH_REQUEST);
-        packet_put_cstring(authctxt->server_user);
-        packet_put_cstring(authctxt->service);
-        packet_put_cstring(authctxt->method->name);
-        packet_send();
+        if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
+            (r = sshpkt_send(ssh)) != 0)
+                fatal("%s: %s", __func__, ssh_err(r));
         return 1;
 }
 
 int
 userauth_passwd(Authctxt *authctxt)
 {
+        struct ssh *ssh = active_state; /* XXX */
         static int attempt = 0;
         char prompt[256];
         char *password;
         const char *host = options.host_key_alias ?  options.host_key_alias :
             authctxt->host;
+        int r;
 
         if (attempt++ >= options.number_of_password_prompts)
                 return 0;
@@ -900,18 +944,20 @@ userauth_passwd(Authctxt *authctxt)
         snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
             authctxt->server_user, host);
         password = read_passphrase(prompt, 0);
-        packet_start(SSH2_MSG_USERAUTH_REQUEST);
-        packet_put_cstring(authctxt->server_user);
-        packet_put_cstring(authctxt->service);
-        packet_put_cstring(authctxt->method->name);
-        packet_put_char(0);
-        packet_put_cstring(password);
-        explicit_bzero(password, strlen(password));
-        free(password);
-        packet_add_padding(64);
-        packet_send();
-
-        dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
+        if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
+            (r = sshpkt_put_u8(ssh, 0)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, password)) != 0 ||
+            (r = sshpkt_add_padding(ssh, 64)) != 0 ||
+            (r = sshpkt_send(ssh)) != 0)
+                fatal("%s: %s", __func__, ssh_err(r));
+
+        if (password)
+                freezero(password, strlen(password));
+
+        ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
             &input_userauth_passwd_changereq);
 
         return 1;
@@ -925,9 +971,10 @@ int
 input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
 {
         Authctxt *authctxt = ssh->authctxt;
-        char *info, *lang, *password = NULL, *retype = NULL;
+        char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
         char prompt[256];
         const char *host;
+        int r;
 
         debug2("input_userauth_passwd_changereq");
 
@@ -936,24 +983,26 @@ input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
                     "no authentication context");
         host = options.host_key_alias ? options.host_key_alias : authctxt->host;
 
-        info = packet_get_string(NULL);
-        lang = packet_get_string(NULL);
+        if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
+            (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
+                goto out;
         if (strlen(info) > 0)
                 logit("%s", info);
-        free(info);
-        free(lang);
-        packet_start(SSH2_MSG_USERAUTH_REQUEST);
-        packet_put_cstring(authctxt->server_user);
-        packet_put_cstring(authctxt->service);
-        packet_put_cstring(authctxt->method->name);
-        packet_put_char(1);                     /* additional info */
+        if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
+            (r = sshpkt_put_u8(ssh, 1)) != 0)   /* additional info */
+                goto out;
+
         snprintf(prompt, sizeof(prompt),
             "Enter %.30s@%.128s's old password: ",
             authctxt->server_user, host);
         password = read_passphrase(prompt, 0);
-        packet_put_cstring(password);
-        explicit_bzero(password, strlen(password));
-        free(password);
+        if ((r = sshpkt_put_cstring(ssh, password)) != 0)
+                goto out;
+
+        freezero(password, strlen(password));
         password = NULL;
         while (password == NULL) {
                 snprintf(prompt, sizeof(prompt),
@@ -962,30 +1011,34 @@ input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
                 password = read_passphrase(prompt, RP_ALLOW_EOF);
                 if (password == NULL) {
                         /* bail out */
-                        return 0;
+                        r = 0;
+                        goto out;
                 }
                 snprintf(prompt, sizeof(prompt),
                     "Retype %.30s@%.128s's new password: ",
                     authctxt->server_user, host);
                 retype = read_passphrase(prompt, 0);
                 if (strcmp(password, retype) != 0) {
-                        explicit_bzero(password, strlen(password));
-                        free(password);
+                        freezero(password, strlen(password));
                         logit("Mismatch; try again, EOF to quit.");
                         password = NULL;
                 }
-                explicit_bzero(retype, strlen(retype));
-                free(retype);
+                freezero(retype, strlen(retype));
         }
-        packet_put_cstring(password);
-        explicit_bzero(password, strlen(password));
-        free(password);
-        packet_add_padding(64);
-        packet_send();
+        if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
+            (r = sshpkt_add_padding(ssh, 64)) != 0 ||
+            (r = sshpkt_send(ssh)) != 0)
+                goto out;
 
-        dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
+        ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
             &input_userauth_passwd_changereq);
-        return 0;
+        r = 0;
+ out:
+        if (password)
+                freezero(password, strlen(password));
+        free(info);
+        free(lang);
+        return r;
 }
 
 /*
@@ -1192,7 +1245,7 @@ sign_and_send_pubkey(struct ssh *ssh, Authctxt *authctxt, Identity *id)
                                     __func__, ssh_err(r));
                         }
                 }
-                skip = buffer_len(b);
+                skip = sshbuf_len(b);
                 if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
                     (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
                     (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
@@ -1259,34 +1312,36 @@ static int
 send_pubkey_test(struct ssh *ssh, Authctxt *authctxt, Identity *id)
 {
         u_char *blob = NULL;
-        u_int bloblen, have_sig = 0;
         char *alg = NULL;
-        int sent = 0;
+        size_t bloblen;
+        u_int have_sig = 0;
+        int sent = 0, r;
 
         if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
                 debug("%s: no mutual signature algorithm", __func__);
                 goto out;
         }
 
-        if (key_to_blob(id->key, &blob, &bloblen) == 0) {
+        if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
                 /* we cannot handle this key */
                 debug3("%s: cannot handle key", __func__);
                 goto out;
         }
         /* register callback for USERAUTH_PK_OK message */
-        dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
-
-        packet_start(SSH2_MSG_USERAUTH_REQUEST);
-        packet_put_cstring(authctxt->server_user);
-        packet_put_cstring(authctxt->service);
-        packet_put_cstring(authctxt->method->name);
-        packet_put_char(have_sig);
-        packet_put_cstring(alg);
-        packet_put_string(blob, bloblen);
-        packet_send();
-        /* success */
+        ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
+
+        if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
+            (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
+            (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
+            (r = sshpkt_send(ssh)) != 0)
+                fatal("%s: %s", __func__, ssh_err(r));
         sent = 1;
-out:
+
+ out:
         free(alg);
         free(blob);
         return sent;
@@ -1347,10 +1402,8 @@ load_identity_file(Identity *id)
                     !(id->key && id->isprivate))
                         maybe_add_key_to_agent(id->filename, private, comment,
                             passphrase);
-                if (i > 0) {
-                        explicit_bzero(passphrase, strlen(passphrase));
-                        free(passphrase);
-                }
+                if (i > 0)
+                        freezero(passphrase, strlen(passphrase));
                 free(comment);
                 if (private != NULL || quit)
                         break;
@@ -1427,7 +1480,7 @@ pubkey_prepare(Authctxt *authctxt)
         /* list of certificates specified by user */
         for (i = 0; i < options.num_certificate_files; i++) {
                 key = options.certificates[i];
-                if (!key_is_cert(key) || key->cert == NULL ||
+                if (!sshkey_is_cert(key) || key->cert == NULL ||
                     key->cert->type != SSH2_CERT_TYPE_USER)
                         continue;
                 id = xcalloc(1, sizeof(*id));
@@ -1501,8 +1554,7 @@ pubkey_prepare(Authctxt *authctxt)
                 /* If IdentitiesOnly set and key not found then don't use it */
                 if (!found && options.identities_only) {
                         TAILQ_REMOVE(&files, id, next);
-                        explicit_bzero(id, sizeof(*id));
-                        free(id);
+                        freezero(id, sizeof(*id));
                 }
         }
         /* append remaining keys from the config file */
@@ -1609,7 +1661,7 @@ userauth_pubkey(Authctxt *authctxt)
                                         sent = sign_and_send_pubkey(ssh,
                                             authctxt, id);
                                 }
-                                key_free(id->key);
+                                sshkey_free(id->key);
                                 id->key = NULL;
                                 id->isprivate = 0;
                         }
@@ -1626,28 +1678,31 @@ userauth_pubkey(Authctxt *authctxt)
 int
 userauth_kbdint(Authctxt *authctxt)
 {
+        struct ssh *ssh = active_state; /* XXX */
         static int attempt = 0;
+        int r;
 
         if (attempt++ >= options.number_of_password_prompts)
                 return 0;
         /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
         if (attempt > 1 && !authctxt->info_req_seen) {
                 debug3("userauth_kbdint: disable: no info_req_seen");
-                dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
+                ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
                 return 0;
         }
 
         debug2("userauth_kbdint");
-        packet_start(SSH2_MSG_USERAUTH_REQUEST);
-        packet_put_cstring(authctxt->server_user);
-        packet_put_cstring(authctxt->service);
-        packet_put_cstring(authctxt->method->name);
-        packet_put_cstring("");                                 /* lang */
-        packet_put_cstring(options.kbd_interactive_devices ?
-            options.kbd_interactive_devices : "");
-        packet_send();
-
-        dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
+        if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
+            (r = sshpkt_put_cstring(ssh, "")) != 0 ||           /* lang */
+            (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
+            options.kbd_interactive_devices : "")) != 0 ||
+            (r = sshpkt_send(ssh)) != 0)
+                fatal("%s: %s", __func__, ssh_err(r));
+
+        ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
         return 1;
 }
 
@@ -1658,9 +1713,11 @@ int
 input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
 {
         Authctxt *authctxt = ssh->authctxt;
-        char *name, *inst, *lang, *prompt, *response;
+        char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
+        char *response = NULL;
+        u_char echo = 0;
         u_int num_prompts, i;
-        int echo = 0;
+        int r;
 
         debug2("input_userauth_info_req");
 
@@ -1669,44 +1726,52 @@ input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
 
         authctxt->info_req_seen = 1;
 
-        name = packet_get_string(NULL);
-        inst = packet_get_string(NULL);
-        lang = packet_get_string(NULL);
+        if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
+            (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
+            (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
+                goto out;
         if (strlen(name) > 0)
                 logit("%s", name);
         if (strlen(inst) > 0)
                 logit("%s", inst);
-        free(name);
-        free(inst);
-        free(lang);
 
-        num_prompts = packet_get_int();
+        if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
+                goto out;
         /*
          * Begin to build info response packet based on prompts requested.
          * We commit to providing the correct number of responses, so if
          * further on we run into a problem that prevents this, we have to
          * be sure and clean this up and send a correct error response.
          */
-        packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
-        packet_put_int(num_prompts);
+        if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
+            (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
+                goto out;
 
         debug2("input_userauth_info_req: num_prompts %d", num_prompts);
         for (i = 0; i < num_prompts; i++) {
-                prompt = packet_get_string(NULL);
-                echo = packet_get_char();
-
+                if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
+                    (r = sshpkt_get_u8(ssh, &echo)) != 0)
+                        goto out;
                 response = read_passphrase(prompt, echo ? RP_ECHO : 0);
-
-                packet_put_cstring(response);
-                explicit_bzero(response, strlen(response));
-                free(response);
+                if ((r = sshpkt_put_cstring(ssh, response)) != 0)
+                        goto out;
+                freezero(response, strlen(response));
                 free(prompt);
+                response = prompt = NULL;
         }
-        packet_check_eom(); /* done with parsing incoming message. */
-
-        packet_add_padding(64);
-        packet_send();
-        return 0;
+        /* done with parsing incoming message. */
+        if ((r = sshpkt_get_end(ssh)) != 0 ||
+            (r = sshpkt_add_padding(ssh, 64)) != 0)
+                goto out;
+        r = sshpkt_send(ssh);
+ out:
+        if (response)
+                freezero(response, strlen(response));
+        free(prompt);
+        free(name);
+        free(inst);
+        free(lang);
+        return r;
 }
 
 static int
@@ -1952,10 +2017,8 @@ userauth_hostbased(Authctxt *authctxt)
         success = 1;
 
  out:
-        if (sig != NULL) {
-                explicit_bzero(sig, siglen);
-                free(sig);
-        }
+        if (sig != NULL)
+                freezero(sig, siglen);
         free(keyblob);
         free(lname);
         free(fp);
@@ -2052,20 +2115,22 @@ static char *
 authmethods_get(void)
 {
         Authmethod *method = NULL;
-        Buffer b;
+        struct sshbuf *b;
         char *list;
+        int r;
 
-        buffer_init(&b);
+        if ((b = sshbuf_new()) == NULL)
+                fatal("%s: sshbuf_new failed", __func__);
         for (method = authmethods; method->name != NULL; method++) {
                 if (authmethod_is_enabled(method)) {
-                        if (buffer_len(&b) > 0)
-                                buffer_append(&b, ",", 1);
-                        buffer_append(&b, method->name, strlen(method->name));
+                        if ((r = sshbuf_putf(b, "%s%s",
+                            sshbuf_len(b) ? "," : "", method->name)) != 0)
+                                fatal("%s: buffer error: %s",
+                                    __func__, ssh_err(r));
                 }
         }
-        if ((list = sshbuf_dup_string(&b)) == NULL)
+        if ((list = sshbuf_dup_string(b)) == NULL)
                 fatal("%s: sshbuf_dup_string failed", __func__);
-        buffer_free(&b);
+        sshbuf_free(b);
         return list;
 }
-