1 files changed, 128 insertions, 0 deletions
diff --git a/src/pty.c b/src/pty.c
new file mode 100644
index 0000000..c888df3
--- /dev/null
+++ b/src/pty.c
@@ -0,0 +1,128 @@
+#include <pty.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <utmp.h>
+
+#include "pty.h"
+
+// callback function for SSH channel PTY request from a client
+int pty_request(ssh_session session, ssh_channel channel,
+                const char *term, int cols, int rows, int py, int px,
+                void *userdata) {
+    struct channel_data_struct *cdata = (struct channel_data_struct *)userdata;
+
+    (void) session;
+    (void) channel;
+    (void) term;
+
+    cdata->winsize->ws_row = rows;
+    cdata->winsize->ws_col = cols;
+    cdata->winsize->ws_xpixel = px;
+    cdata->winsize->ws_ypixel = py;
+
+    if (openpty(&cdata->pty_master, &cdata->pty_slave, NULL, NULL,
+                cdata->winsize) != 0) {
+        fprintf(stderr, "Failed to open pty\n");
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+// callback function for SSH channel PTY resize from a client
+int pty_resize(ssh_session session, ssh_channel channel, int cols,
+               int rows, int py, int px, void *userdata) {
+    struct channel_data_struct *cdata = (struct channel_data_struct *)userdata;
+
+    (void) session;
+    (void) channel;
+
+    cdata->winsize->ws_row = rows;
+    cdata->winsize->ws_col = cols;
+    cdata->winsize->ws_xpixel = px;
+    cdata->winsize->ws_ypixel = py;
+
+    if (cdata->pty_master != -1) {
+        return ioctl(cdata->pty_master, TIOCSWINSZ, cdata->winsize);
+    }
+
+    return SSH_ERROR;
+}
+
+int exec_pty(const char *mode, const char *command,
+             struct channel_data_struct *cdata) {
+    switch(cdata->pid = fork()) {
+        case -1:
+            close(cdata->pty_master);
+            close(cdata->pty_slave);
+            fprintf(stderr, "Failed to fork\n");
+            return SSH_ERROR;
+        case 0:
+            close(cdata->pty_master);
+            if (login_tty(cdata->pty_slave) != 0) {
+                exit(1);
+            }
+            execl("/bin/sh", "sh", mode, command, NULL);
+            exit(0);
+        default:
+            close(cdata->pty_slave);
+            /* pty fd is bi-directional */
+            cdata->child_stdout = cdata->child_stdin = cdata->pty_master;
+    }
+    return SSH_OK;
+}
+
+int exec_nopty(const char *command, struct channel_data_struct *cdata) {
+    int in[2], out[2], err[2];
+
+    /* Do the plumbing to be able to talk with the child process. */
+    if (pipe(in) != 0) {
+        goto stdin_failed;
+    }
+    if (pipe(out) != 0) {
+        goto stdout_failed;
+    }
+    if (pipe(err) != 0) {
+        goto stderr_failed;
+    }
+
+    switch(cdata->pid = fork()) {
+        case -1:
+            goto fork_failed;
+        case 0:
+            /* Finish the plumbing in the child process. */
+            close(in[1]);
+            close(out[0]);
+            close(err[0]);
+            dup2(in[0], STDIN_FILENO);
+            dup2(out[1], STDOUT_FILENO);
+            dup2(err[1], STDERR_FILENO);
+            close(in[0]);
+            close(out[1]);
+            close(err[1]);
+            /* exec the requested command. */
+            execl("/bin/sh", "sh", "-c", command, NULL);
+            exit(0);
+    }
+
+    close(in[0]);
+    close(out[1]);
+    close(err[1]);
+
+    cdata->child_stdin = in[1];
+    cdata->child_stdout = out[0];
+    cdata->child_stderr = err[0];
+
+    return SSH_OK;
+
+fork_failed:
+    close(err[0]);
+    close(err[1]);
+stderr_failed:
+    close(out[0]);
+    close(out[1]);
+stdout_failed:
+    close(in[0]);
+    close(in[1]);
+stdin_failed:
+    return SSH_ERROR;
+}