vfs: Implement syscalls

2026-10-25 19:47:43 +01:00
parent 244618dbeb
commit eb86ea3622
11 changed files with 1823 additions and 205 deletions
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: ISC
+
+#include <zinnia/alloc.h>
+#include <zinnia/ident.h>
+#include <zinnia/print.h>
+#include <zinnia/spin.h>
+#include <zinnia/syscall.h>
+#include <zinnia/usercopy.h>
+#include <arch/archctl.h>
+#include <config.h>
+#include <stdint.h>
+#include <string.h>
+#include <uapi/utsname.h>
+#include "internal.h"
+
+enum syslog_kind : uintptr_t {
+    SYSLOG_EMERG = 0,
+    SYSLOG_ALERT = 1,
+    SYSLOG_CRIT = 2,
+    SYSLOG_ERR = 3,
+    SYSLOG_WARNING = 4,
+    SYSLOG_NOTICE = 5,
+    SYSLOG_INFO = 6,
+    SYSLOG_DEBUG = 7,
+};
+
+static struct spinlock uname_lock = {};
+
+static struct __utsname uname_buf = {
+    .sysname = "Zinnia",
+    .release = ZINNIA_VERSION,
+    .version = CONFIG_KERNEL_FLAVOR,
+    .nodename = "localhost",
+    .machine = ZINNIA_ARCH,
+    .domainname = "(none)",
+};
+
+struct syscall_ret sys_archctl(uintptr_t op, uintptr_t arg) {
+    return arch_archctl(op, arg);
+}
+
+struct syscall_ret sys_getuname(__user struct __utsname* ptr) {
+    struct syscall_ret ret = {};
+
+    if (!ptr) {
+        ret.error = EINVAL;
+        return ret;
+    }
+
+    spin_lock(&uname_lock);
+    struct __utsname write_buf = uname_buf;
+    spin_unlock(&uname_lock);
+
+    if (!usercopy_write(ptr, &write_buf, sizeof(write_buf)))
+        ret.error = EFAULT;
+
+    return ret;
+}
+
+struct syscall_ret sys_setuname(const __user struct __utsname* ptr) {
+    struct syscall_ret ret = {};
+
+    if (!ptr) {
+        ret.error = EINVAL;
+        return ret;
+    }
+
+    if (!ident_is_privileged(&self()->identity, false)) {
+        ret.error = EPERM;
+        return ret;
+    }
+
+    struct __utsname read_buf;
+    if (!usercopy_read(&read_buf, ptr, sizeof(read_buf))) {
+        ret.error = EFAULT;
+        return ret;
+    }
+
+    spin_lock(&uname_lock);
+
+    strncpy(uname_buf.sysname, read_buf.sysname, sizeof(uname_buf.sysname) - 1);
+    strncpy(uname_buf.release, read_buf.release, sizeof(uname_buf.release) - 1);
+    strncpy(uname_buf.version, read_buf.version, sizeof(uname_buf.version) - 1);
+    strncpy(uname_buf.nodename, read_buf.nodename, sizeof(uname_buf.nodename) - 1);
+    strncpy(uname_buf.machine, read_buf.machine, sizeof(uname_buf.machine) - 1);
+    strncpy(uname_buf.domainname, read_buf.domainname, sizeof(uname_buf.domainname) - 1);
+
+    spin_unlock(&uname_lock);
+
+    return ret;
+}
+
+struct syscall_ret sys_syslog(enum syslog_kind kind, __user char* message, size_t len) {
+    struct syscall_ret ret = {};
+
+    const size_t buf_len = MIN(len + 1, 256);
+    char* buf = mem_alloc(buf_len, ALLOC_NOZERO);
+    if (!usercopy_read(buf, message, buf_len - 1)) {
+        mem_free(buf);
+
+        ret.error = EFAULT;
+        return ret;
+    }
+    buf[buf_len - 1] = 0;
+
+    const char* log_level;
+    switch (kind) {
+    case SYSLOG_EMERG:
+        log_level = "emerg";
+        break;
+    case SYSLOG_ALERT:
+        log_level = "alert";
+        break;
+    case SYSLOG_CRIT:
+        log_level = "crit";
+        break;
+    case SYSLOG_ERR:
+        log_level = "err";
+        break;
+    case SYSLOG_WARNING:
+        log_level = "warning";
+        break;
+    case SYSLOG_NOTICE:
+        log_level = "notice";
+        break;
+    case SYSLOG_INFO:
+        log_level = "info";
+        break;
+    case SYSLOG_DEBUG:
+        log_level = "debug";
+        break;
+    default:
+        log_level = "invalid";
+    }
+
+    log("syslog(%s): %s\n", log_level, buf);
+
+    mem_free(buf);
+
+    return ret;
+}