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

OpenBSD-Commit-ID: 60cb0356114acc7625ab85105f6f6a7cd44a8d05

1 files changed, 113 insertions, 89 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);