mirror of
https://github.com/zrepl/zrepl.git
synced 2024-12-22 23:20:51 +01:00
70bbdfe760
Developed for #285 but ultimately not used for it.
307 lines
9.0 KiB
Go
307 lines
9.0 KiB
Go
package zfs
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"os/exec"
|
|
"regexp"
|
|
"strconv"
|
|
"strings"
|
|
"sync"
|
|
"time"
|
|
|
|
"github.com/pkg/errors"
|
|
|
|
"github.com/zrepl/zrepl/util/envconst"
|
|
"github.com/zrepl/zrepl/zfs/zfscmd"
|
|
)
|
|
|
|
// NOTE: Update ZFSSendARgs.Validate when changing fields (potentially SECURITY SENSITIVE)
|
|
type ResumeToken struct {
|
|
HasFromGUID, HasToGUID bool
|
|
FromGUID, ToGUID uint64
|
|
ToName string
|
|
HasCompressOK, CompressOK bool
|
|
HasRawOk, RawOK bool
|
|
HasLargeBlockOK, LargeBlockOK bool
|
|
HasEmbedOk, EmbedOK bool
|
|
HasSavedOk, SavedOk bool
|
|
}
|
|
|
|
var resumeTokenNVListRE = regexp.MustCompile(`\t(\S+) = (.*)`)
|
|
|
|
var resumeTokenContentsRE = regexp.MustCompile(`resume token contents:\nnvlist version: 0`)
|
|
var resumeTokenIsCorruptRE = regexp.MustCompile(`resume token is corrupt`)
|
|
|
|
var ResumeTokenCorruptError = errors.New("resume token is corrupt")
|
|
var ResumeTokenDecodingNotSupported = errors.New("zfs binary does not allow decoding resume token or zrepl cannot scrape zfs output")
|
|
var ResumeTokenParsingError = errors.New("zrepl cannot parse resume token values")
|
|
|
|
var resumeSendSupportedCheck struct {
|
|
once sync.Once
|
|
supported bool
|
|
err error
|
|
}
|
|
|
|
func ResumeSendSupported(ctx context.Context) (bool, error) {
|
|
resumeSendSupportedCheck.once.Do(func() {
|
|
// "feature discovery"
|
|
cmd := zfscmd.CommandContext(ctx, "zfs", "send")
|
|
output, err := cmd.CombinedOutput()
|
|
if ee, ok := err.(*exec.ExitError); !ok || ok && !ee.Exited() {
|
|
resumeSendSupportedCheck.err = errors.Wrap(err, "resumable send cli support feature check failed")
|
|
}
|
|
def := strings.Contains(string(output), "receive_resume_token")
|
|
resumeSendSupportedCheck.supported = envconst.Bool("ZREPL_EXPERIMENTAL_ZFS_SEND_RESUME_SUPPORTED", def)
|
|
debug("resume send feature check complete %#v", &resumeSendSupportedCheck)
|
|
})
|
|
return resumeSendSupportedCheck.supported, resumeSendSupportedCheck.err
|
|
}
|
|
|
|
var resumeRecvPoolSupportRecheckTimeout = envconst.Duration("ZREPL_ZFS_RESUME_RECV_POOL_SUPPORT_RECHECK_TIMEOUT", 30*time.Second)
|
|
|
|
type resumeRecvPoolSupportedResult struct {
|
|
lastCheck time.Time
|
|
supported bool
|
|
err error
|
|
}
|
|
|
|
var resumeRecvSupportedCheck struct {
|
|
mtx sync.RWMutex
|
|
flagSupport struct {
|
|
checked bool
|
|
supported bool
|
|
err error
|
|
}
|
|
poolSupported map[string]resumeRecvPoolSupportedResult
|
|
}
|
|
|
|
// fs == nil only checks for CLI support
|
|
func ResumeRecvSupported(ctx context.Context, fs *DatasetPath) (bool, error) {
|
|
sup := &resumeRecvSupportedCheck
|
|
sup.mtx.RLock()
|
|
defer sup.mtx.RUnlock()
|
|
upgradeWhile := func(cb func()) {
|
|
sup.mtx.RUnlock()
|
|
defer sup.mtx.RLock()
|
|
sup.mtx.Lock()
|
|
defer sup.mtx.Unlock()
|
|
cb()
|
|
}
|
|
|
|
if !sup.flagSupport.checked {
|
|
output, err := zfscmd.CommandContext(ctx, ZFS_BINARY, "receive").CombinedOutput()
|
|
upgradeWhile(func() {
|
|
sup.flagSupport.checked = true
|
|
if ee, ok := err.(*exec.ExitError); err != nil && (!ok || ok && !ee.Exited()) {
|
|
sup.flagSupport.err = err
|
|
} else {
|
|
sup.flagSupport.supported = strings.Contains(string(output), "-A <filesystem|volume>")
|
|
}
|
|
debug("resume recv cli flag feature check result: %#v", sup.flagSupport)
|
|
})
|
|
// fallthrough
|
|
}
|
|
|
|
if sup.flagSupport.err != nil {
|
|
return false, errors.Wrap(sup.flagSupport.err, "zfs recv feature check for resumable send & recv failed")
|
|
} else if !sup.flagSupport.supported || fs == nil {
|
|
return sup.flagSupport.supported, nil
|
|
}
|
|
|
|
// Flag is supported and pool-support is request
|
|
// Now check for pool support
|
|
|
|
pool, err := fs.Pool()
|
|
if err != nil {
|
|
return false, errors.Wrap(err, "resume recv check requires pool of dataset")
|
|
}
|
|
|
|
if sup.poolSupported == nil {
|
|
upgradeWhile(func() {
|
|
sup.poolSupported = make(map[string]resumeRecvPoolSupportedResult)
|
|
})
|
|
}
|
|
|
|
var poolSup resumeRecvPoolSupportedResult
|
|
var ok bool
|
|
if poolSup, ok = sup.poolSupported[pool]; !ok || // shadow
|
|
(!poolSup.supported && time.Since(poolSup.lastCheck) > resumeRecvPoolSupportRecheckTimeout) {
|
|
|
|
output, err := zfscmd.CommandContext(ctx, "zpool", "get", "-H", "-p", "-o", "value", "feature@extensible_dataset", pool).CombinedOutput()
|
|
if err != nil {
|
|
debug("resume recv pool support check result: %#v", sup.flagSupport)
|
|
poolSup.supported = false
|
|
poolSup.err = err
|
|
} else {
|
|
poolSup.err = nil
|
|
o := strings.TrimSpace(string(output))
|
|
poolSup.supported = o == "active" || o == "enabled"
|
|
}
|
|
poolSup.lastCheck = time.Now()
|
|
|
|
// we take the lock late, so two updaters might check simultaneously, but that shouldn't hurt
|
|
upgradeWhile(func() {
|
|
sup.poolSupported[pool] = poolSup
|
|
})
|
|
// fallthrough
|
|
}
|
|
|
|
if poolSup.err != nil {
|
|
return false, errors.Wrapf(poolSup.err, "pool %q check for feature@extensible_dataset feature failed", pool)
|
|
}
|
|
|
|
return poolSup.supported, nil
|
|
}
|
|
|
|
// Abuse 'zfs send' to decode the resume token
|
|
//
|
|
// FIXME: implement nvlist unpacking in Go and read through libzfs_sendrecv.c
|
|
func ParseResumeToken(ctx context.Context, token string) (*ResumeToken, error) {
|
|
|
|
if supported, err := ResumeSendSupported(ctx); err != nil {
|
|
return nil, err
|
|
} else if !supported {
|
|
return nil, ResumeTokenDecodingNotSupported
|
|
}
|
|
|
|
// Example resume tokens:
|
|
//
|
|
// From a non-incremental send
|
|
// 1-bf31b879a-b8-789c636064000310a500c4ec50360710e72765a5269740f80cd8e4d3d28a534b18e00024cf86249f5459925acc802a8facbf243fbd3433858161f5ddb9ab1ae7c7466a20c97382e5f312735319180af2f3730cf58166953824c2cc0200cde81651
|
|
|
|
// From an incremental send
|
|
// 1-c49b979a2-e0-789c636064000310a501c49c50360710a715e5e7a69766a63040c1eabb735735ce8f8d5400b2d991d4e52765a5269740f82080219f96569c5ac2000720793624f9a4ca92d46206547964fd25f91057f09e37babb88c9bf5503499e132c9f97989bcac050909f9f63a80f34abc421096616007c881d4c
|
|
|
|
// Resulting output of zfs send -nvt <token>
|
|
//
|
|
//resume token contents:
|
|
//nvlist version: 0
|
|
// fromguid = 0x595d9f81aa9dddab
|
|
// object = 0x1
|
|
// offset = 0x0
|
|
// bytes = 0x0
|
|
// toguid = 0x854f02a2dd32cf0d
|
|
// toname = pool1/test@b
|
|
//cannot resume send: 'pool1/test@b' used in the initial send no longer exists
|
|
|
|
cmd := zfscmd.CommandContext(ctx, ZFS_BINARY, "send", "-nvt", string(token))
|
|
output, err := cmd.CombinedOutput()
|
|
if err != nil {
|
|
if exitErr, ok := err.(*exec.ExitError); ok {
|
|
if !exitErr.Exited() {
|
|
return nil, err
|
|
}
|
|
// we abuse zfs send for decoding, the exit error may be due to
|
|
// a) the token being from a third machine
|
|
// b) it no longer exists on the machine where
|
|
} else {
|
|
return nil, err
|
|
}
|
|
}
|
|
|
|
if !resumeTokenContentsRE.Match(output) {
|
|
if resumeTokenIsCorruptRE.Match(output) {
|
|
return nil, ResumeTokenCorruptError
|
|
}
|
|
return nil, ResumeTokenDecodingNotSupported
|
|
}
|
|
|
|
matches := resumeTokenNVListRE.FindAllStringSubmatch(string(output), -1)
|
|
if matches == nil {
|
|
return nil, ResumeTokenDecodingNotSupported
|
|
}
|
|
|
|
rt := &ResumeToken{}
|
|
|
|
for _, m := range matches {
|
|
attr, val := m[1], m[2]
|
|
switch attr {
|
|
case "fromguid":
|
|
rt.FromGUID, err = strconv.ParseUint(val, 0, 64)
|
|
if err != nil {
|
|
return nil, ResumeTokenParsingError
|
|
}
|
|
rt.HasFromGUID = true
|
|
case "toguid":
|
|
rt.ToGUID, err = strconv.ParseUint(val, 0, 64)
|
|
if err != nil {
|
|
return nil, ResumeTokenParsingError
|
|
}
|
|
rt.HasToGUID = true
|
|
case "toname":
|
|
rt.ToName = val
|
|
case "rawok":
|
|
rt.HasRawOk = true
|
|
rt.RawOK, err = strconv.ParseBool(val)
|
|
if err != nil {
|
|
return nil, ResumeTokenParsingError
|
|
}
|
|
case "compressok":
|
|
rt.HasCompressOK = true
|
|
rt.CompressOK, err = strconv.ParseBool(val)
|
|
if err != nil {
|
|
return nil, ResumeTokenParsingError
|
|
}
|
|
case "embedok":
|
|
rt.HasEmbedOk = true
|
|
rt.EmbedOK, err = strconv.ParseBool(val)
|
|
if err != nil {
|
|
return nil, ResumeTokenParsingError
|
|
}
|
|
case "largeblockok":
|
|
rt.HasLargeBlockOK = true
|
|
rt.LargeBlockOK, err = strconv.ParseBool(val)
|
|
if err != nil {
|
|
return nil, ResumeTokenParsingError
|
|
}
|
|
case "savedok":
|
|
rt.HasSavedOk = true
|
|
rt.SavedOk, err = strconv.ParseBool(val)
|
|
if err != nil {
|
|
return nil, ResumeTokenParsingError
|
|
}
|
|
}
|
|
}
|
|
|
|
if !rt.HasToGUID {
|
|
return nil, ResumeTokenDecodingNotSupported
|
|
}
|
|
|
|
return rt, nil
|
|
|
|
}
|
|
|
|
// if string is empty and err == nil, the feature is not supported
|
|
func ZFSGetReceiveResumeTokenOrEmptyStringIfNotSupported(ctx context.Context, fs *DatasetPath) (string, error) {
|
|
if supported, err := ResumeRecvSupported(ctx, fs); err != nil {
|
|
return "", errors.Wrap(err, "cannot determine zfs recv resume support")
|
|
} else if !supported {
|
|
return "", nil
|
|
}
|
|
const prop_receive_resume_token = "receive_resume_token"
|
|
props, err := ZFSGet(ctx, fs, []string{prop_receive_resume_token})
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
res := props.Get(prop_receive_resume_token)
|
|
debug("%q receive_resume_token=%q", fs.ToString(), res)
|
|
if res == "-" {
|
|
return "", nil
|
|
} else {
|
|
return res, nil
|
|
}
|
|
}
|
|
|
|
func (t *ResumeToken) ToNameSplit() (fs *DatasetPath, snapName string, err error) {
|
|
comps := strings.SplitN(t.ToName, "@", 2)
|
|
if len(comps) != 2 {
|
|
return nil, "", fmt.Errorf("resume token field `toname` does not contain @: %q", t.ToName)
|
|
}
|
|
dp, err := NewDatasetPath(comps[0])
|
|
if err != nil {
|
|
return nil, "", errors.Wrap(err, "resume token field `toname` dataset path invalid")
|
|
}
|
|
return dp, comps[1], nil
|
|
}
|