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_f("Failed to get the path to SELinux context"); + return; + } + + if ((contexts_file = fopen(contexts_path, "r")) == NULL) { + debug_f("Failed to open SELinux context file"); + return; + } + + if (fstat(fileno(contexts_file), &sb) != 0 || + sb.st_uid != 0 || (sb.st_mode & 022) != 0) { + logit_f("SELinux context file needs to be owned by root" + " and not writable by anyone else"); + 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_f("privsep_preauth is empty"); + fclose(contexts_file); + return; + } + preauth_context = xstrdup(arg); + } + } + fclose(contexts_file); + + if (preauth_context == NULL) { + debug_f("Unable to find 'privsep_preauth' option in" + " SELinux context file"); + 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 --- a/openbsd-compat/port-linux.c (revision 8241b9c0529228b4b86d88b1a6076fb9f97e4a99) +++ b/openbsd-compat/port-linux.c (date 1703108053912) @@ -207,7 +207,7 @@ xasprintf(&newctx, "%.*s%s%s", (int)(cx - oldctx + 1), oldctx, newname, cx2 == NULL ? "" : cx2); - debug3_f("setting context from '%s' to '%s'", oldctx, newctx); + debug_f("setting context from '%s' to '%s'", oldctx, newctx); if (setcon(newctx) < 0) do_log2_f(log_level, "setcon %s from %s failed with %s", newctx, oldctx, strerror(errno)); 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-session.c b/sshd-session.c index 2871fe9..39b9c08 100644 --- a/sshd-session.c +++ b/sshd-session.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 */