[PULL 21/51] bsd-user: Implement procctl(2) along with necessary conversion functions.

[Warner Losh <imp@bsdimp.com>]

From: Stacey Son <sson@FreeBSD.org>

Implement t2h_procctl_cmd, h2t_reaper_status, h2t_reaper_pidinfo and h2t/t2h reaper_kill conversion functions.

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Karim Taha <kariem.taha2.7@gmail.com>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20230925182425.3163-22-kariem.taha2.7@gmail.com>
---
 bsd-user/freebsd/os-proc.c    | 223 ++++++++++++++++++++++++++++++++++
 bsd-user/freebsd/os-syscall.c |   3 +
 2 files changed, 226 insertions(+)

diff --git a/bsd-user/freebsd/os-proc.c b/bsd-user/freebsd/os-proc.c
index 12d78b7fc98..4e67ae4d56c 100644
--- a/bsd-user/freebsd/os-proc.c
+++ b/bsd-user/freebsd/os-proc.c
@@ -255,3 +255,226 @@ execve_end:
     return ret;
 }
 
+#include <sys/procctl.h>
+
+static abi_long
+t2h_procctl_cmd(int target_cmd, int *host_cmd)
+{
+    switch (target_cmd) {
+    case TARGET_PROC_SPROTECT:
+        *host_cmd = PROC_SPROTECT;
+        break;
+
+    case TARGET_PROC_REAP_ACQUIRE:
+        *host_cmd = PROC_REAP_ACQUIRE;
+        break;
+
+    case TARGET_PROC_REAP_RELEASE:
+        *host_cmd = PROC_REAP_RELEASE;
+        break;
+
+    case TARGET_PROC_REAP_STATUS:
+        *host_cmd = PROC_REAP_STATUS;
+        break;
+
+    case TARGET_PROC_REAP_KILL:
+        *host_cmd = PROC_REAP_KILL;
+        break;
+
+    default:
+        return -TARGET_EINVAL;
+    }
+
+    return 0;
+}
+
+static abi_long
+h2t_reaper_status(struct procctl_reaper_status *host_rs,
+        abi_ulong target_rs_addr)
+{
+    struct target_procctl_reaper_status *target_rs;
+
+    if (!lock_user_struct(VERIFY_WRITE, target_rs, target_rs_addr, 0)) {
+        return -TARGET_EFAULT;
+    }
+    __put_user(host_rs->rs_flags, &target_rs->rs_flags);
+    __put_user(host_rs->rs_children, &target_rs->rs_children);
+    __put_user(host_rs->rs_descendants, &target_rs->rs_descendants);
+    __put_user(host_rs->rs_reaper, &target_rs->rs_reaper);
+    __put_user(host_rs->rs_pid, &target_rs->rs_pid);
+    unlock_user_struct(target_rs, target_rs_addr, 1);
+
+    return 0;
+}
+
+static abi_long
+t2h_reaper_kill(abi_ulong target_rk_addr, struct procctl_reaper_kill *host_rk)
+{
+    struct target_procctl_reaper_kill *target_rk;
+
+    if (!lock_user_struct(VERIFY_READ, target_rk, target_rk_addr, 1)) {
+        return -TARGET_EFAULT;
+    }
+    __get_user(host_rk->rk_sig, &target_rk->rk_sig);
+    __get_user(host_rk->rk_flags, &target_rk->rk_flags);
+    __get_user(host_rk->rk_subtree, &target_rk->rk_subtree);
+    __get_user(host_rk->rk_killed, &target_rk->rk_killed);
+    __get_user(host_rk->rk_fpid, &target_rk->rk_fpid);
+    unlock_user_struct(target_rk, target_rk_addr, 0);
+
+    return 0;
+}
+
+static abi_long
+h2t_reaper_kill(struct procctl_reaper_kill *host_rk, abi_ulong target_rk_addr)
+{
+    struct target_procctl_reaper_kill *target_rk;
+
+    if (!lock_user_struct(VERIFY_WRITE, target_rk, target_rk_addr, 0)) {
+        return -TARGET_EFAULT;
+    }
+    __put_user(host_rk->rk_sig, &target_rk->rk_sig);
+    __put_user(host_rk->rk_flags, &target_rk->rk_flags);
+    __put_user(host_rk->rk_subtree, &target_rk->rk_subtree);
+    __put_user(host_rk->rk_killed, &target_rk->rk_killed);
+    __put_user(host_rk->rk_fpid, &target_rk->rk_fpid);
+    unlock_user_struct(target_rk, target_rk_addr, 1);
+
+    return 0;
+}
+
+static abi_long
+h2t_procctl_reaper_pidinfo(struct procctl_reaper_pidinfo *host_pi,
+        abi_ulong target_pi_addr)
+{
+    struct target_procctl_reaper_pidinfo *target_pi;
+
+    if (!lock_user_struct(VERIFY_WRITE, target_pi, target_pi_addr, 0)) {
+        return -TARGET_EFAULT;
+    }
+    __put_user(host_pi->pi_pid, &target_pi->pi_pid);
+    __put_user(host_pi->pi_subtree, &target_pi->pi_subtree);
+    __put_user(host_pi->pi_flags, &target_pi->pi_flags);
+    unlock_user_struct(target_pi, target_pi_addr, 1);
+
+    return 0;
+}
+
+abi_long
+do_freebsd_procctl(void *cpu_env, int idtype, abi_ulong arg2, abi_ulong arg3,
+       abi_ulong arg4, abi_ulong arg5, abi_ulong arg6)
+{
+    abi_long error = 0, target_rp_pids;
+    void *data;
+    int host_cmd, flags;
+    uint32_t u, target_rp_count;
+    g_autofree union {
+        struct procctl_reaper_status rs;
+        struct procctl_reaper_pids rp;
+        struct procctl_reaper_kill rk;
+    } host;
+    struct target_procctl_reaper_pids *target_rp;
+    id_t id; /* 64-bit */
+    int target_cmd;
+    abi_ulong target_arg;
+
+#if TARGET_ABI_BITS == 32
+    /* See if we need to align the register pairs. */
+    if (regpairs_aligned(cpu_env)) {
+        id = (id_t)target_arg64(arg3, arg4);
+        target_cmd = (int)arg5;
+        target_arg = arg6;
+    } else {
+        id = (id_t)target_arg64(arg2, arg3);
+        target_cmd = (int)arg4;
+        target_arg = arg5;
+    }
+#else
+    id = (id_t)arg2;
+    target_cmd = (int)arg3;
+    target_arg = arg4;
+#endif
+
+    error = t2h_procctl_cmd(target_cmd, &host_cmd);
+    if (error) {
+        return error;
+    }
+    switch (host_cmd) {
+    case PROC_SPROTECT:
+        data = &flags;
+        break;
+
+    case PROC_REAP_ACQUIRE:
+    case PROC_REAP_RELEASE:
+        if (target_arg == 0) {
+            data = NULL;
+        } else {
+            error = -TARGET_EINVAL;
+        }
+        break;
+
+    case PROC_REAP_STATUS:
+        data = &host.rs;
+        break;
+
+    case PROC_REAP_GETPIDS:
+        if (!lock_user_struct(VERIFY_READ, target_rp, target_arg, 1)) {
+            return -TARGET_EFAULT;
+        }
+        __get_user(target_rp_count, &target_rp->rp_count);
+        __get_user(target_rp_pids, &target_rp->rp_pids);
+        unlock_user_struct(target_rp, target_arg, 0);
+        host.rp.rp_count = target_rp_count;
+        host.rp.rp_pids = g_try_new(struct procctl_reaper_pidinfo,
+            target_rp_count);
+
+        if (host.rp.rp_pids == NULL) {
+            error = -TARGET_ENOMEM;
+        } else {
+            data = &host.rp;
+        }
+        break;
+
+    case PROC_REAP_KILL:
+        error = t2h_reaper_kill(target_arg, &host.rk);
+        break;
+    }
+
+    if (error) {
+        return error;
+    }
+    error = get_errno(procctl(idtype, id, host_cmd, data));
+
+    if (error) {
+        return error;
+    }
+    switch (host_cmd) {
+    case PROC_SPROTECT:
+        if (put_user_s32(flags, target_arg)) {
+            return -TARGET_EFAULT;
+        }
+        break;
+
+    case PROC_REAP_STATUS:
+        error = h2t_reaper_status(&host.rs, target_arg);
+        break;
+
+    case PROC_REAP_GETPIDS:
+        /* copyout reaper pidinfo */
+        for (u = 0; u < target_rp_count; u++) {
+            error = h2t_procctl_reaper_pidinfo(&host.rp.rp_pids[u],
+                    target_rp_pids +
+                    (u * sizeof(struct target_procctl_reaper_pidinfo)));
+            if (error) {
+                break;
+            }
+        }
+        break;
+
+    case PROC_REAP_KILL:
+        error = h2t_reaper_kill(&host.rk, target_arg);
+        break;
+    }
+
+    return error;
+}
diff --git a/bsd-user/freebsd/os-syscall.c b/bsd-user/freebsd/os-syscall.c
index 71a2657dd0f..b7bd0b92a65 100644
--- a/bsd-user/freebsd/os-syscall.c
+++ b/bsd-user/freebsd/os-syscall.c
@@ -367,6 +367,9 @@ static abi_long freebsd_syscall(void *cpu_env, int num, abi_long arg1,
         ret = do_bsd_setpriority(arg1, arg2, arg3);
         break;
 
+    case TARGET_FREEBSD_NR_procctl: /* procctl(2) */
+        ret = do_freebsd_procctl(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
+        break;
 
         /*
          * File system calls.
-- 
2.41.0