freebsd-dev/sys/kern/kern_environment.c

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/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 1998 Michael Smith
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
1998-10-09 11:03:46 +00:00
*/
/*
* The unified bootloader passes us a pointer to a preserved copy of
* bootstrap/kernel environment variables. We convert them to a
* dynamic array of strings later when the VM subsystem is up.
*
* We make these available through the kenv(2) syscall for userland
* and through kern_getenv()/freeenv() kern_setenv() kern_unsetenv() testenv() for
* the kernel.
*/
2003-06-11 00:56:59 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/priv.h>
#include <sys/kenv.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/sysent.h>
#include <sys/sysproto.h>
#include <sys/libkern.h>
#include <sys/kenv.h>
#include <sys/limits.h>
#include <security/mac/mac_framework.h>
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
static char *_getenv_dynamic_locked(const char *name, int *idx);
static char *_getenv_dynamic(const char *name, int *idx);
static char *kenv_acquire(const char *name);
static void kenv_release(const char *buf);
static MALLOC_DEFINE(M_KENV, "kenv", "kernel environment");
#define KENV_SIZE 512 /* Maximum number of environment strings */
static uma_zone_t kenv_zone;
static int kenv_mvallen = KENV_MVALLEN;
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
/* pointer to the config-generated static environment */
char *kern_envp;
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
/* pointer to the md-static environment */
char *md_envp;
static int md_env_len;
static int md_env_pos;
static char *kernenv_next(char *);
/* dynamic environment variables */
char **kenvp;
struct mtx kenv_lock;
/*
* No need to protect this with a mutex since SYSINITS are single threaded.
*/
bool dynamic_kenv;
#define KENV_CHECK if (!dynamic_kenv) \
panic("%s: called before SI_SUB_KMEM", __func__)
int
sys_kenv(td, uap)
struct thread *td;
struct kenv_args /* {
int what;
const char *name;
char *value;
int len;
} */ *uap;
{
char *name, *value, *buffer = NULL;
size_t len, done, needed, buflen;
int error, i;
KASSERT(dynamic_kenv, ("kenv: dynamic_kenv = false"));
error = 0;
2002-12-14 01:56:26 +00:00
if (uap->what == KENV_DUMP) {
#ifdef MAC
error = mac_kenv_check_dump(td->td_ucred);
if (error)
return (error);
#endif
done = needed = 0;
buflen = uap->len;
if (buflen > KENV_SIZE * (KENV_MNAMELEN + kenv_mvallen + 2))
buflen = KENV_SIZE * (KENV_MNAMELEN +
kenv_mvallen + 2);
if (uap->len > 0 && uap->value != NULL)
buffer = malloc(buflen, M_TEMP, M_WAITOK|M_ZERO);
mtx_lock(&kenv_lock);
for (i = 0; kenvp[i] != NULL; i++) {
len = strlen(kenvp[i]) + 1;
needed += len;
len = min(len, buflen - done);
/*
* If called with a NULL or insufficiently large
* buffer, just keep computing the required size.
*/
if (uap->value != NULL && buffer != NULL && len > 0) {
bcopy(kenvp[i], buffer + done, len);
done += len;
}
}
mtx_unlock(&kenv_lock);
if (buffer != NULL) {
error = copyout(buffer, uap->value, done);
free(buffer, M_TEMP);
}
td->td_retval[0] = ((done == needed) ? 0 : needed);
return (error);
}
switch (uap->what) {
case KENV_SET:
error = priv_check(td, PRIV_KENV_SET);
if (error)
return (error);
break;
case KENV_UNSET:
error = priv_check(td, PRIV_KENV_UNSET);
if (error)
return (error);
break;
}
name = malloc(KENV_MNAMELEN + 1, M_TEMP, M_WAITOK);
error = copyinstr(uap->name, name, KENV_MNAMELEN + 1, NULL);
if (error)
goto done;
2002-12-14 01:56:26 +00:00
switch (uap->what) {
case KENV_GET:
#ifdef MAC
error = mac_kenv_check_get(td->td_ucred, name);
if (error)
goto done;
#endif
value = kern_getenv(name);
if (value == NULL) {
error = ENOENT;
goto done;
}
len = strlen(value) + 1;
2002-12-14 01:56:26 +00:00
if (len > uap->len)
len = uap->len;
error = copyout(value, uap->value, len);
freeenv(value);
if (error)
goto done;
td->td_retval[0] = len;
break;
case KENV_SET:
2002-12-14 01:56:26 +00:00
len = uap->len;
if (len < 1) {
error = EINVAL;
goto done;
}
if (len > kenv_mvallen + 1)
len = kenv_mvallen + 1;
value = malloc(len, M_TEMP, M_WAITOK);
2002-12-14 01:56:26 +00:00
error = copyinstr(uap->value, value, len, NULL);
if (error) {
free(value, M_TEMP);
goto done;
}
#ifdef MAC
error = mac_kenv_check_set(td->td_ucred, name, value);
if (error == 0)
#endif
kern_setenv(name, value);
free(value, M_TEMP);
break;
case KENV_UNSET:
#ifdef MAC
error = mac_kenv_check_unset(td->td_ucred, name);
if (error)
goto done;
#endif
error = kern_unsetenv(name);
if (error)
error = ENOENT;
break;
default:
error = EINVAL;
break;
}
done:
free(name, M_TEMP);
return (error);
}
Make the 'env' directive described in config(5) work on all architectures, providing compiled-in static environment data that is used instead of any data passed in from a boot loader. Previously 'env' worked only on i386 and arm xscale systems, because it required the MD startup code to examine the global envmode variable and decide whether to use static_env or an environment obtained from the boot loader, and set the global kern_envp accordingly. Most startup code wasn't doing so. Making things even more complex, some mips startup code uses an alternate scheme that involves calling init_static_kenv() to pass an empty buffer and its size, then uses a series of kern_setenv() calls to populate that buffer. Now all MD startup code calls init_static_kenv(), and that routine provides a single point where envmode is checked and the decision is made whether to use the compiled-in static_kenv or the values provided by the MD code. The routine also continues to serve its original purpose for mips; if a non-zero buffer size is passed the routine installs the empty buffer ready to accept kern_setenv() values. Now if the size is zero, the provided buffer full of existing env data is installed. A NULL pointer can be passed if the boot loader provides no env data; this allows the static env to be installed if envmode is set to do so. Most of the work here is a near-mechanical change to call the init function instead of directly setting kern_envp. A notable exception is in xen/pv.c; that code was originally installing a buffer full of preformatted env data along with its non-zero size (like mips code does), which would have allowed kern_setenv() calls to wipe out the preformatted data. Now it passes a zero for the size so that the buffer of data it installs is treated as non-writeable.
2016-01-02 02:53:48 +00:00
/*
* Populate the initial kernel environment.
*
* This is called very early in MD startup, either to provide a copy of the
* environment obtained from a boot loader, or to provide an empty buffer into
* which MD code can store an initial environment using kern_setenv() calls.
*
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
* kern_envp is set to the static_env generated by config(8). This implements
* the env keyword described in config(5).
Make the 'env' directive described in config(5) work on all architectures, providing compiled-in static environment data that is used instead of any data passed in from a boot loader. Previously 'env' worked only on i386 and arm xscale systems, because it required the MD startup code to examine the global envmode variable and decide whether to use static_env or an environment obtained from the boot loader, and set the global kern_envp accordingly. Most startup code wasn't doing so. Making things even more complex, some mips startup code uses an alternate scheme that involves calling init_static_kenv() to pass an empty buffer and its size, then uses a series of kern_setenv() calls to populate that buffer. Now all MD startup code calls init_static_kenv(), and that routine provides a single point where envmode is checked and the decision is made whether to use the compiled-in static_kenv or the values provided by the MD code. The routine also continues to serve its original purpose for mips; if a non-zero buffer size is passed the routine installs the empty buffer ready to accept kern_setenv() values. Now if the size is zero, the provided buffer full of existing env data is installed. A NULL pointer can be passed if the boot loader provides no env data; this allows the static env to be installed if envmode is set to do so. Most of the work here is a near-mechanical change to call the init function instead of directly setting kern_envp. A notable exception is in xen/pv.c; that code was originally installing a buffer full of preformatted env data along with its non-zero size (like mips code does), which would have allowed kern_setenv() calls to wipe out the preformatted data. Now it passes a zero for the size so that the buffer of data it installs is treated as non-writeable.
2016-01-02 02:53:48 +00:00
*
* If len is non-zero, the caller is providing an empty buffer. The caller will
* subsequently use kern_setenv() to add up to len bytes of initial environment
* before the dynamic environment is available.
*
* If len is zero, the caller is providing a pre-loaded buffer containing
* environment strings. Additional strings cannot be added until the dynamic
* environment is available. The memory pointed to must remain stable at least
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
* until sysinit runs init_dynamic_kenv() and preferably until after SI_SUB_KMEM
* is finished so that subr_hints routines may continue to use it until the
* environments have been fully merged at the end of the pass. If no initial
* environment is available from the boot loader, passing a NULL pointer allows
* the static_env to be installed if it is configured. In this case, any call
* to kern_setenv() prior to the setup of the dynamic environment will result in
* a panic.
Make the 'env' directive described in config(5) work on all architectures, providing compiled-in static environment data that is used instead of any data passed in from a boot loader. Previously 'env' worked only on i386 and arm xscale systems, because it required the MD startup code to examine the global envmode variable and decide whether to use static_env or an environment obtained from the boot loader, and set the global kern_envp accordingly. Most startup code wasn't doing so. Making things even more complex, some mips startup code uses an alternate scheme that involves calling init_static_kenv() to pass an empty buffer and its size, then uses a series of kern_setenv() calls to populate that buffer. Now all MD startup code calls init_static_kenv(), and that routine provides a single point where envmode is checked and the decision is made whether to use the compiled-in static_kenv or the values provided by the MD code. The routine also continues to serve its original purpose for mips; if a non-zero buffer size is passed the routine installs the empty buffer ready to accept kern_setenv() values. Now if the size is zero, the provided buffer full of existing env data is installed. A NULL pointer can be passed if the boot loader provides no env data; this allows the static env to be installed if envmode is set to do so. Most of the work here is a near-mechanical change to call the init function instead of directly setting kern_envp. A notable exception is in xen/pv.c; that code was originally installing a buffer full of preformatted env data along with its non-zero size (like mips code does), which would have allowed kern_setenv() calls to wipe out the preformatted data. Now it passes a zero for the size so that the buffer of data it installs is treated as non-writeable.
2016-01-02 02:53:48 +00:00
*/
void
init_static_kenv(char *buf, size_t len)
{
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
KASSERT(!dynamic_kenv, ("kenv: dynamic_kenv already initialized"));
/*
* Suitably sized means it must be able to hold at least one empty
* variable, otherwise things go belly up if a kern_getenv call is
* made without a prior call to kern_setenv as we have a malformed
* environment.
*/
KASSERT(len == 0 || len >= 2,
("kenv: static env must be initialized or suitably sized"));
KASSERT(len == 0 || (*buf == '\0' && *(buf + 1) == '\0'),
("kenv: sized buffer must be initially empty"));
/*
* We may be called twice, with the second call needed to relocate
* md_envp after enabling paging. md_envp is then garbage if it is
* not null and the relocation will move it. Discard it so as to
* not crash using its old value in our first call to kern_getenv().
*
* The second call gives the same environment as the first except
* in silly configurations where the static env disables itself.
*
* Other env calls don't handle possibly-garbage pointers, so must
* not be made between enabling paging and calling here.
*/
md_envp = NULL;
md_env_len = 0;
md_env_pos = 0;
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
/*
* Give the static environment a chance to disable the loader(8)
* environment first. This is done with loader_env.disabled=1.
*
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
* static_env and static_hints may both be disabled, but in slightly
* different ways. For static_env, we just don't setup kern_envp and
* it's as if a static env wasn't even provided. For static_hints,
* we effectively zero out the buffer to stop the rest of the kernel
* from being able to use it.
*
* We're intentionally setting this up so that static_hints.disabled may
* be specified in either the MD env or the static env. This keeps us
* consistent in our new world view.
*
* As a warning, the static environment may not be disabled in any way
* if the static environment has disabled the loader environment.
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
*/
kern_envp = static_env;
if (!getenv_is_true("loader_env.disabled")) {
md_envp = buf;
md_env_len = len;
md_env_pos = 0;
if (getenv_is_true("static_env.disabled")) {
kern_envp[0] = '\0';
kern_envp[1] = '\0';
}
}
if (getenv_is_true("static_hints.disabled")) {
static_hints[0] = '\0';
static_hints[1] = '\0';
}
}
static void
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
init_dynamic_kenv_from(char *init_env, int *curpos)
{
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
char *cp, *cpnext, *eqpos, *found;
size_t len;
int i;
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
if (init_env && *init_env != '\0') {
found = NULL;
i = *curpos;
for (cp = init_env; cp != NULL; cp = cpnext) {
cpnext = kernenv_next(cp);
len = strlen(cp) + 1;
if (len > KENV_MNAMELEN + 1 + kenv_mvallen + 1) {
printf(
"WARNING: too long kenv string, ignoring %s\n",
cp);
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
goto sanitize;
}
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
eqpos = strchr(cp, '=');
if (eqpos == NULL) {
printf(
"WARNING: malformed static env value, ignoring %s\n",
cp);
goto sanitize;
}
*eqpos = 0;
/*
* De-dupe the environment as we go. We don't add the
* duplicated assignments because config(8) will flip
* the order of the static environment around to make
* kernel processing match the order of specification
* in the kernel config.
*/
found = _getenv_dynamic_locked(cp, NULL);
*eqpos = '=';
if (found != NULL)
goto sanitize;
if (i > KENV_SIZE) {
printf(
"WARNING: too many kenv strings, ignoring %s\n",
cp);
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
goto sanitize;
}
kenvp[i] = malloc(len, M_KENV, M_WAITOK);
strcpy(kenvp[i++], cp);
sanitize:
explicit_bzero(cp, len - 1);
}
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
*curpos = i;
}
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
}
/*
* Setup the dynamic kernel environment.
*/
static void
init_dynamic_kenv(void *data __unused)
{
int dynamic_envpos;
int size;
TUNABLE_INT_FETCH("kenv_mvallen", &kenv_mvallen);
size = KENV_MNAMELEN + 1 + kenv_mvallen + 1;
kenv_zone = uma_zcreate("kenv", size, NULL, NULL, NULL, NULL,
UMA_ALIGN_PTR, 0);
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
kenvp = malloc((KENV_SIZE + 1) * sizeof(char *), M_KENV,
M_WAITOK | M_ZERO);
dynamic_envpos = 0;
init_dynamic_kenv_from(md_envp, &dynamic_envpos);
init_dynamic_kenv_from(kern_envp, &dynamic_envpos);
kenvp[dynamic_envpos] = NULL;
mtx_init(&kenv_lock, "kernel environment", NULL, MTX_DEF);
dynamic_kenv = true;
}
SYSINIT(kenv, SI_SUB_KMEM + 1, SI_ORDER_FIRST, init_dynamic_kenv, NULL);
void
freeenv(char *env)
{
if (dynamic_kenv && env != NULL) {
explicit_bzero(env, strlen(env));
uma_zfree(kenv_zone, env);
}
}
/*
* Internal functions for string lookup.
*/
static char *
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
_getenv_dynamic_locked(const char *name, int *idx)
{
char *cp;
int len, i;
len = strlen(name);
for (cp = kenvp[0], i = 0; cp != NULL; cp = kenvp[++i]) {
if ((strncmp(cp, name, len) == 0) &&
(cp[len] == '=')) {
if (idx != NULL)
*idx = i;
return (cp + len + 1);
}
}
return (NULL);
}
static char *
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
_getenv_dynamic(const char *name, int *idx)
{
mtx_assert(&kenv_lock, MA_OWNED);
return (_getenv_dynamic_locked(name, idx));
}
static char *
_getenv_static_from(char *chkenv, const char *name)
{
char *cp, *ep;
int len;
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
for (cp = chkenv; cp != NULL; cp = kernenv_next(cp)) {
for (ep = cp; (*ep != '=') && (*ep != 0); ep++)
;
if (*ep != '=')
continue;
len = ep - cp;
ep++;
if (!strncmp(name, cp, len) && name[len] == 0)
return (ep);
}
return (NULL);
}
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
static char *
_getenv_static(const char *name)
{
char *val;
val = _getenv_static_from(md_envp, name);
if (val != NULL)
return (val);
val = _getenv_static_from(kern_envp, name);
if (val != NULL)
return (val);
return (NULL);
}
/*
* Look up an environment variable by name.
* Return a pointer to the string if found.
* The pointer has to be freed with freeenv()
* after use.
*/
char *
kern_getenv(const char *name)
{
char *cp, *ret;
int len;
if (dynamic_kenv) {
len = KENV_MNAMELEN + 1 + kenv_mvallen + 1;
ret = uma_zalloc(kenv_zone, M_WAITOK | M_ZERO);
mtx_lock(&kenv_lock);
cp = _getenv_dynamic(name, NULL);
if (cp != NULL)
strlcpy(ret, cp, len);
mtx_unlock(&kenv_lock);
if (cp == NULL) {
uma_zfree(kenv_zone, ret);
ret = NULL;
}
} else
ret = _getenv_static(name);
return (ret);
}
/*
* Test if an environment variable is defined.
*/
int
testenv(const char *name)
{
char *cp;
cp = kenv_acquire(name);
kenv_release(cp);
if (cp != NULL)
return (1);
return (0);
}
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
/*
* Set an environment variable in the MD-static environment. This cannot
* feasibly be done on config(8)-generated static environments as they don't
* generally include space for extra variables.
*/
static int
setenv_static(const char *name, const char *value)
{
int len;
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
if (md_env_pos >= md_env_len)
return (-1);
/* Check space for x=y and two nuls */
len = strlen(name) + strlen(value);
kern_environment: use any provided environments, evict hintmode/envmode At the moment, hintmode and envmode are used to indicate whether static hints or static env have been provided in the kernel config(5) and the static versions are mutually exclusive with loader(8)-provided environment. hintmode *can* be reconfigured later to pull from the dynamic environment, thus taking advantage of the loader(8) or post-kmem environment setting. This changeset fixes both problems at once to move us from a semi-confusing state to a consistent state: if an environment file, hints file, or loader(8) environment are provided, we use them in a well-known order of precedence: - loader(8) environment - static environment - static hints file Once the dynamic environment is setup this becomes a moot point. The loader(8) and static environments are merged (respecting the above order of precedence), and the static hints are merged in on an as-needed basis after the dynamic environment has been setup. Hints lookup are changed to respect all of the above. Before the dynamic environment is setup, lookups use the above-mentioned order and fallback to the next environment if a matching hint is not found. Once the dynamic environment is setup, that is used on its own since it captures all of the above information plus any dynamic kenv settings that came up later in boot. The following tangentially related changes were made to res_find: - A hintp cookie is now passed in so that related searches continue using the chain of environments (or dynamic environment) without relying on global state - All three environments will be searched if they actually have valid hints to use, rather than just choosing the first environment that actually had a hint and rolling with that only The hintmode sysctl has been ripped out. static_{env,hints}.disabled are still honored and will disable their respective environments from being used for hint lookups and from being merged into the dynamic environment, as expected. MFC after: 1 month (maybe) Differential Revision: https://reviews.freebsd.org/D15953
2018-07-05 16:30:32 +00:00
if (len + 3 < md_env_len - md_env_pos) {
len = sprintf(&md_envp[md_env_pos], "%s=%s", name, value);
md_env_pos += len+1;
md_envp[md_env_pos] = '\0';
return (0);
} else
return (-1);
}
/*
* Set an environment variable by name.
*/
int
kern_setenv(const char *name, const char *value)
{
char *buf, *cp, *oldenv;
int namelen, vallen, i;
if (!dynamic_kenv && md_env_len > 0)
return (setenv_static(name, value));
KENV_CHECK;
namelen = strlen(name) + 1;
if (namelen > KENV_MNAMELEN + 1)
return (-1);
vallen = strlen(value) + 1;
if (vallen > kenv_mvallen + 1)
return (-1);
buf = malloc(namelen + vallen, M_KENV, M_WAITOK);
sprintf(buf, "%s=%s", name, value);
mtx_lock(&kenv_lock);
cp = _getenv_dynamic(name, &i);
if (cp != NULL) {
oldenv = kenvp[i];
kenvp[i] = buf;
mtx_unlock(&kenv_lock);
free(oldenv, M_KENV);
} else {
/* We add the option if it wasn't found */
for (i = 0; (cp = kenvp[i]) != NULL; i++)
;
/* Bounds checking */
if (i < 0 || i >= KENV_SIZE) {
free(buf, M_KENV);
mtx_unlock(&kenv_lock);
return (-1);
}
kenvp[i] = buf;
kenvp[i + 1] = NULL;
mtx_unlock(&kenv_lock);
}
return (0);
}
/*
* Unset an environment variable string.
*/
int
kern_unsetenv(const char *name)
{
char *cp, *oldenv;
int i, j;
KENV_CHECK;
mtx_lock(&kenv_lock);
cp = _getenv_dynamic(name, &i);
if (cp != NULL) {
oldenv = kenvp[i];
for (j = i + 1; kenvp[j] != NULL; j++)
kenvp[i++] = kenvp[j];
kenvp[i] = NULL;
mtx_unlock(&kenv_lock);
zfree(oldenv, M_KENV);
return (0);
}
mtx_unlock(&kenv_lock);
return (-1);
}
/*
* Return the internal kenv buffer for the variable name, if it exists.
* If the dynamic kenv is initialized and the name is present, return
* with kenv_lock held.
*/
static char *
kenv_acquire(const char *name)
{
char *value;
if (dynamic_kenv) {
mtx_lock(&kenv_lock);
value = _getenv_dynamic(name, NULL);
if (value == NULL)
mtx_unlock(&kenv_lock);
return (value);
} else
return (_getenv_static(name));
}
/*
* Undo a previous kenv_acquire() operation
*/
static void
kenv_release(const char *buf)
{
if ((buf != NULL) && dynamic_kenv)
mtx_unlock(&kenv_lock);
}
/*
* Return a string value from an environment variable.
*/
int
getenv_string(const char *name, char *data, int size)
{
char *cp;
cp = kenv_acquire(name);
if (cp != NULL)
strlcpy(data, cp, size);
kenv_release(cp);
return (cp != NULL);
}
/*
* Return an array of integers at the given type size and signedness.
*/
int
getenv_array(const char *name, void *pdata, int size, int *psize,
int type_size, bool allow_signed)
{
uint8_t shift;
int64_t value;
int64_t old;
const char *buf;
char *end;
const char *ptr;
int n;
int rc;
rc = 0; /* assume failure */
buf = kenv_acquire(name);
if (buf == NULL)
goto error;
/* get maximum number of elements */
size /= type_size;
n = 0;
for (ptr = buf; *ptr != 0; ) {
value = strtoq(ptr, &end, 0);
/* check if signed numbers are allowed */
if (value < 0 && !allow_signed)
goto error;
/* check for invalid value */
if (ptr == end)
goto error;
/* check for valid suffix */
switch (*end) {
case 't':
case 'T':
shift = 40;
end++;
break;
case 'g':
case 'G':
shift = 30;
end++;
break;
case 'm':
case 'M':
shift = 20;
end++;
break;
case 'k':
case 'K':
shift = 10;
end++;
break;
case ' ':
case '\t':
case ',':
case 0:
shift = 0;
break;
default:
/* garbage after numeric value */
goto error;
}
/* skip till next value, if any */
while (*end == '\t' || *end == ',' || *end == ' ')
end++;
/* update pointer */
ptr = end;
/* apply shift */
old = value;
value <<= shift;
/* overflow check */
if ((value >> shift) != old)
goto error;
/* check for buffer overflow */
if (n >= size)
goto error;
/* store value according to type size */
switch (type_size) {
case 1:
if (allow_signed) {
if (value < SCHAR_MIN || value > SCHAR_MAX)
goto error;
} else {
if (value < 0 || value > UCHAR_MAX)
goto error;
}
((uint8_t *)pdata)[n] = (uint8_t)value;
break;
case 2:
if (allow_signed) {
if (value < SHRT_MIN || value > SHRT_MAX)
goto error;
} else {
if (value < 0 || value > USHRT_MAX)
goto error;
}
((uint16_t *)pdata)[n] = (uint16_t)value;
break;
case 4:
if (allow_signed) {
if (value < INT_MIN || value > INT_MAX)
goto error;
} else {
if (value > UINT_MAX)
goto error;
}
((uint32_t *)pdata)[n] = (uint32_t)value;
break;
case 8:
((uint64_t *)pdata)[n] = (uint64_t)value;
break;
default:
goto error;
}
n++;
}
*psize = n * type_size;
if (n != 0)
rc = 1; /* success */
error:
kenv_release(buf);
return (rc);
}
/*
* Return an integer value from an environment variable.
*/
int
getenv_int(const char *name, int *data)
1999-11-07 01:10:30 +00:00
{
quad_t tmp;
int rval;
rval = getenv_quad(name, &tmp);
if (rval)
*data = (int) tmp;
return (rval);
1999-11-07 01:10:30 +00:00
}
/*
* Return an unsigned integer value from an environment variable.
*/
int
getenv_uint(const char *name, unsigned int *data)
{
quad_t tmp;
int rval;
rval = getenv_quad(name, &tmp);
if (rval)
*data = (unsigned int) tmp;
return (rval);
}
/*
* Return an int64_t value from an environment variable.
*/
int
getenv_int64(const char *name, int64_t *data)
{
quad_t tmp;
int64_t rval;
rval = getenv_quad(name, &tmp);
if (rval)
*data = (int64_t) tmp;
return (rval);
}
/*
* Return an uint64_t value from an environment variable.
*/
int
getenv_uint64(const char *name, uint64_t *data)
{
quad_t tmp;
uint64_t rval;
rval = getenv_quad(name, &tmp);
if (rval)
*data = (uint64_t) tmp;
return (rval);
}
/*
* Return a long value from an environment variable.
*/
int
getenv_long(const char *name, long *data)
{
quad_t tmp;
int rval;
rval = getenv_quad(name, &tmp);
if (rval)
*data = (long) tmp;
return (rval);
}
/*
* Return an unsigned long value from an environment variable.
*/
int
getenv_ulong(const char *name, unsigned long *data)
{
quad_t tmp;
int rval;
rval = getenv_quad(name, &tmp);
if (rval)
*data = (unsigned long) tmp;
return (rval);
}
1999-11-07 01:10:30 +00:00
/*
* Return a quad_t value from an environment variable.
*/
int
getenv_quad(const char *name, quad_t *data)
{
const char *value;
char suffix, *vtp;
quad_t iv;
value = kenv_acquire(name);
if (value == NULL) {
goto error;
}
iv = strtoq(value, &vtp, 0);
if (vtp == value || (vtp[0] != '\0' && vtp[1] != '\0')) {
goto error;
}
suffix = vtp[0];
kenv_release(value);
switch (suffix) {
case 't': case 'T':
iv *= 1024;
/* FALLTHROUGH */
case 'g': case 'G':
iv *= 1024;
/* FALLTHROUGH */
case 'm': case 'M':
iv *= 1024;
/* FALLTHROUGH */
case 'k': case 'K':
iv *= 1024;
case '\0':
break;
default:
return (0);
}
*data = iv;
return (1);
error:
kenv_release(value);
return (0);
}
/*
* Return a boolean value from an environment variable. This can be in
* numerical or string form, i.e. "1" or "true".
*/
int
getenv_bool(const char *name, bool *data)
{
char *val;
int ret = 0;
if (name == NULL)
return (0);
val = kern_getenv(name);
if (val == NULL)
return (0);
if ((strcmp(val, "1") == 0) || (strcasecmp(val, "true") == 0)) {
*data = true;
ret = 1;
} else if ((strcmp(val, "0") == 0) || (strcasecmp(val, "false") == 0)) {
*data = false;
ret = 1;
} else {
/* Spit out a warning for malformed boolean variables. */
printf("Environment variable %s has non-boolean value \"%s\"\n",
name, val);
}
freeenv(val);
return (ret);
}
/*
* Wrapper around getenv_bool to easily check for true.
*/
bool
getenv_is_true(const char *name)
{
bool val;
if (getenv_bool(name, &val) != 0)
return (val);
return (false);
}
/*
* Wrapper around getenv_bool to easily check for false.
*/
bool
getenv_is_false(const char *name)
{
bool val;
if (getenv_bool(name, &val) != 0)
return (!val);
return (false);
}
/*
* Find the next entry after the one which (cp) falls within, return a
* pointer to its start or NULL if there are no more.
*/
static char *
kernenv_next(char *cp)
{
if (cp != NULL) {
while (*cp != 0)
cp++;
cp++;
if (*cp == 0)
cp = NULL;
}
return (cp);
}
void
tunable_int_init(void *data)
{
struct tunable_int *d = (struct tunable_int *)data;
TUNABLE_INT_FETCH(d->path, d->var);
}
void
tunable_long_init(void *data)
{
struct tunable_long *d = (struct tunable_long *)data;
TUNABLE_LONG_FETCH(d->path, d->var);
}
void
tunable_ulong_init(void *data)
{
struct tunable_ulong *d = (struct tunable_ulong *)data;
TUNABLE_ULONG_FETCH(d->path, d->var);
}
void
tunable_int64_init(void *data)
{
struct tunable_int64 *d = (struct tunable_int64 *)data;
TUNABLE_INT64_FETCH(d->path, d->var);
}
void
tunable_uint64_init(void *data)
{
struct tunable_uint64 *d = (struct tunable_uint64 *)data;
TUNABLE_UINT64_FETCH(d->path, d->var);
}
void
tunable_quad_init(void *data)
{
struct tunable_quad *d = (struct tunable_quad *)data;
TUNABLE_QUAD_FETCH(d->path, d->var);
}
void
tunable_bool_init(void *data)
{
struct tunable_bool *d = (struct tunable_bool *)data;
TUNABLE_BOOL_FETCH(d->path, d->var);
}
void
tunable_str_init(void *data)
{
struct tunable_str *d = (struct tunable_str *)data;
TUNABLE_STR_FETCH(d->path, d->var, d->size);
}