+#include "pathnames.h"
+#include "log.h"
+#include "ssh.h"
+
+static char *
+ssh_askpass(char *askpass, const char *msg)
+{
+ pid_t pid;
+ size_t len;
+ char *pass;
+ int p[2], status, ret;
+ char buf[1024];
+
+ if (fflush(stdout) != 0)
+ error("ssh_askpass: fflush: %s", strerror(errno));
+ if (askpass == NULL)
+ fatal("internal error: askpass undefined");
+ if (pipe(p) < 0) {
+ error("ssh_askpass: pipe: %s", strerror(errno));
+ return xstrdup("");
+ }
+ if ((pid = fork()) < 0) {
+ error("ssh_askpass: fork: %s", strerror(errno));
+ return xstrdup("");
+ }
+ if (pid == 0) {
+ seteuid(getuid());
+ setuid(getuid());
+ close(p[0]);
+ if (dup2(p[1], STDOUT_FILENO) < 0)
+ fatal("ssh_askpass: dup2: %s", strerror(errno));
+ execlp(askpass, askpass, msg, (char *) 0);
+ fatal("ssh_askpass: exec(%s): %s", askpass, strerror(errno));
+ }
+ close(p[1]);
+
+ len = ret = 0;
+ do {
+ ret = read(p[0], buf + len, sizeof(buf) - 1 - len);
+ if (ret == -1 && errno == EINTR)
+ continue;
+ if (ret <= 0)
+ break;
+ len += ret;
+ } while (sizeof(buf) - 1 - len > 0);
+ buf[len] = '\0';
+
+ close(p[0]);
+ while (waitpid(pid, &status, 0) < 0)
+ if (errno != EINTR)
+ break;
+
+ buf[strcspn(buf, "\r\n")] = '\0';
+ pass = xstrdup(buf);
+ memset(buf, 0, sizeof(buf));
+ return pass;
+}