diff --git a/openbsd-compat/port-linux-sshd.c b/openbsd-compat/port-linux-sshd.c index 8f32464..18a2ca4 100644 --- a/openbsd-compat/port-linux-sshd.c +++ b/openbsd-compat/port-linux-sshd.c @@ -32,6 +32,7 @@ #include "misc.h" /* servconf.h needs misc.h for struct ForwardOptions */ #include "servconf.h" #include "port-linux.h" +#include "misc.h" #include "sshkey.h" #include "hostfile.h" #include "auth.h" @@ -445,7 +446,7 @@ sshd_selinux_setup_exec_context(char *pwname) void sshd_selinux_copy_context(void) { - security_context_t *ctx; + char *ctx; if (!sshd_selinux_enabled()) return; @@ -461,6 +462,72 @@ sshd_selinux_copy_context(void) } } +void +sshd_selinux_change_privsep_preauth_context(void) +{ + int len; + char line[1024], *preauth_context = NULL, *cp, *arg; + const char *contexts_path; + FILE *contexts_file; + struct stat sb; + + contexts_path = selinux_openssh_contexts_path(); + if (contexts_path == NULL) { + debug3("%s: Failed to get the path to SELinux context", __func__); + return; + } + + if ((contexts_file = fopen(contexts_path, "r")) == NULL) { + debug("%s: Failed to open SELinux context file", __func__); + return; + } + + if (fstat(fileno(contexts_file), &sb) != 0 || + sb.st_uid != 0 || (sb.st_mode & 022) != 0) { + logit("%s: SELinux context file needs to be owned by root" + " and not writable by anyone else", __func__); + fclose(contexts_file); + return; + } + + while (fgets(line, sizeof(line), contexts_file)) { + /* Strip trailing whitespace */ + for (len = strlen(line) - 1; len > 0; len--) { + if (strchr(" \t\r\n", line[len]) == NULL) + break; + line[len] = '\0'; + } + + if (line[0] == '\0') + continue; + + cp = line; + arg = strdelim(&cp); + if (arg && *arg == '\0') + arg = strdelim(&cp); + + if (arg && strcmp(arg, "privsep_preauth") == 0) { + arg = strdelim(&cp); + if (!arg || *arg == '\0') { + debug("%s: privsep_preauth is empty", __func__); + fclose(contexts_file); + return; + } + preauth_context = xstrdup(arg); + } + } + fclose(contexts_file); + + if (preauth_context == NULL) { + debug("%s: Unable to find 'privsep_preauth' option in" + " SELinux context file", __func__); + return; + } + + ssh_selinux_change_context(preauth_context); + free(preauth_context); +} + #endif #endif diff --git a/openbsd-compat/port-linux.c b/openbsd-compat/port-linux.c index 22ea8ef..1fc963d 100644 --- a/openbsd-compat/port-linux.c +++ b/openbsd-compat/port-linux.c @@ -179,7 +179,7 @@ ssh_selinux_change_context(const char *newname) strlcpy(newctx + len, newname, newlen - len); if ((cx = index(cx + 1, ':'))) strlcat(newctx, cx, newlen); - debug3("%s: setting context from '%s' to '%s'", __func__, + debug("%s: setting context from '%s' to '%s'", __func__, oldctx, newctx); if (setcon(newctx) < 0) switchlog("%s: setcon %s from %s failed with %s", __func__, diff --git a/openbsd-compat/port-linux.h b/openbsd-compat/port-linux.h index cb51f99..8b7cda2 100644 --- a/openbsd-compat/port-linux.h +++ b/openbsd-compat/port-linux.h @@ -29,6 +29,7 @@ int sshd_selinux_enabled(void); void sshd_selinux_copy_context(void); void sshd_selinux_setup_exec_context(char *); int sshd_selinux_setup_env_variables(void); +void sshd_selinux_change_privsep_preauth_context(void); #endif #ifdef LINUX_OOM_ADJUST diff --git a/sshd.c b/sshd.c index 2871fe9..39b9c08 100644 --- a/sshd.c +++ b/sshd.c @@ -629,7 +629,7 @@ privsep_preauth_child(void) demote_sensitive_data(); #ifdef WITH_SELINUX - ssh_selinux_change_context("sshd_net_t"); + sshd_selinux_change_privsep_preauth_context(); #endif /* Demote the child */