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Copy file name to clipboardExpand all lines: CHANGELOG-3.2.md
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### Security, Authentication
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- Fix [TLS reload](TODO) when [cert SAN field only contains IP addresses](https://github.com/coreos/etcd/issues/9541).
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- Fix [TLS reload](https://github.com/coreos/etcd/pull/9570) when [certificate SAN field only includes IP addresses but no domain names](https://github.com/coreos/etcd/issues/9541).
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- In Go, server calls `(*tls.Config).GetCertificate` for TLS reload if and only if server's `(*tls.Config).Certificates` field is not empty, or `(*tls.ClientHelloInfo).ServerName` is not empty with a valid SNI from the client. Previously, etcd always populates `(*tls.Config).Certificates` on the initial client TLS handshake, as non-empty. Thus, client was always expected to supply a matching SNI in order to pass the TLS verification and to trigger `(*tls.Config).GetCertificate` to reload TLS assets.
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- However, a certificate whose SAN field does [not include any domain names but only IP addresses](https://github.com/coreos/etcd/issues/9541) would request `*tls.ClientHelloInfo` with an empty `ServerName` field, thus failing to trigger the TLS reload on initial TLS handshake; this becomes a problem when expired certificates need to be replaced online.
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- Now, `(*tls.Config).Certificates` is created empty on initial TLS client handshake, first to trigger `(*tls.Config).GetCertificate`, and then to populate rest of the certificates on every new TLS connection, even when client SNI is empty (e.g. cert only includes IPs).
Copy file name to clipboardExpand all lines: CHANGELOG-3.3.md
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### Security, Authentication
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- Fix [TLS reload](TODO) when [cert SAN field only contains IP addresses](https://github.com/coreos/etcd/issues/9541).
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- Fix [TLS reload](https://github.com/coreos/etcd/pull/9570) when [certificate SAN field only includes IP addresses but no domain names](https://github.com/coreos/etcd/issues/9541).
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- In Go, server calls `(*tls.Config).GetCertificate` for TLS reload if and only if server's `(*tls.Config).Certificates` field is not empty, or `(*tls.ClientHelloInfo).ServerName` is not empty with a valid SNI from the client. Previously, etcd always populates `(*tls.Config).Certificates` on the initial client TLS handshake, as non-empty. Thus, client was always expected to supply a matching SNI in order to pass the TLS verification and to trigger `(*tls.Config).GetCertificate` to reload TLS assets.
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- However, a certificate whose SAN field does [not include any domain names but only IP addresses](https://github.com/coreos/etcd/issues/9541) would request `*tls.ClientHelloInfo` with an empty `ServerName` field, thus failing to trigger the TLS reload on initial TLS handshake; this becomes a problem when expired certificates need to be replaced online.
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- Now, `(*tls.Config).Certificates` is created empty on initial TLS client handshake, first to trigger `(*tls.Config).GetCertificate`, and then to populate rest of the certificates on every new TLS connection, even when client SNI is empty (e.g. cert only includes IPs).
Copy file name to clipboardExpand all lines: CHANGELOG-3.4.md
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- Support [`ttl` field for `etcd` Authentication JWT token](https://github.com/coreos/etcd/pull/8302).
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- e.g. `etcd --auth-token jwt,pub-key=<pub key path>,priv-key=<priv key path>,sign-method=<sign method>,ttl=5m`.
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- Allow empty token provider in [`etcdserver.ServerConfig.AuthToken`](https://github.com/coreos/etcd/pull/9369).
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- Fix [TLS reload](TODO) when [cert SAN field only contains IP addresses](https://github.com/coreos/etcd/issues/9541).
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- Fix [TLS reload](https://github.com/coreos/etcd/pull/9570) when [certificate SAN field only includes IP addresses but no domain names](https://github.com/coreos/etcd/issues/9541).
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- In Go, server calls `(*tls.Config).GetCertificate` for TLS reload if and only if server's `(*tls.Config).Certificates` field is not empty, or `(*tls.ClientHelloInfo).ServerName` is not empty with a valid SNI from the client. Previously, etcd always populates `(*tls.Config).Certificates` on the initial client TLS handshake, as non-empty. Thus, client was always expected to supply a matching SNI in order to pass the TLS verification and to trigger `(*tls.Config).GetCertificate` to reload TLS assets.
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- However, a certificate whose SAN field does [not include any domain names but only IP addresses](https://github.com/coreos/etcd/issues/9541) would request `*tls.ClientHelloInfo` with an empty `ServerName` field, thus failing to trigger the TLS reload on initial TLS handshake; this becomes a problem when expired certificates need to be replaced online.
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- Now, `(*tls.Config).Certificates` is created empty on initial TLS client handshake, first to trigger `(*tls.Config).GetCertificate`, and then to populate rest of the certificates on every new TLS connection, even when client SNI is empty (e.g. cert only includes IPs).
Copy file name to clipboardExpand all lines: Documentation/op-guide/security.md
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I | embed: serving client requests on 127.0.0.1:2379
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```
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[v3.2.19](https://github.com/coreos/etcd/blob/master/CHANGELOG-3.2.md) and [v3.3.4](https://github.com/coreos/etcd/blob/master/CHANGELOG-3.3.md) fixes TLS reload when [certificate SAN field only includes IP addresses but no domain names](https://github.com/coreos/etcd/issues/9541). For example, a member is set up with CSRs (with `cfssl`) as below:
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```json
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{
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"CN": "etcd.local",
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"hosts": [
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"127.0.0.1"
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],
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```
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In Go, server calls `(*tls.Config).GetCertificate` for TLS reload if and only if server's `(*tls.Config).Certificates` field is not empty, or `(*tls.ClientHelloInfo).ServerName` is not empty with a valid SNI from the client. Previously, etcd always populates `(*tls.Config).Certificates` on the initial client TLS handshake, as non-empty. Thus, client was always expected to supply a matching SNI in order to pass the TLS verification and to trigger `(*tls.Config).GetCertificate` to reload TLS assets.
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However, a certificate whose SAN field does [not include any domain names but only IP addresses](https://github.com/coreos/etcd/issues/9541) would request `*tls.ClientHelloInfo` with an empty `ServerName` field, thus failing to trigger the TLS reload on initial TLS handshake; this becomes a problem when expired certificates need to be replaced online.
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Now, `(*tls.Config).Certificates` is created empty on initial TLS client handshake, first to trigger `(*tls.Config).GetCertificate`, and then to populate rest of the certificates on every new TLS connection, even when client SNI is empty (e.g. cert only includes IPs).
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## Notes for Host Whitelist
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`etcd --host-whitelist` flag specifies acceptable hostnames from HTTP client requests. Client origin policy protects against ["DNS Rebinding"](https://en.wikipedia.org/wiki/DNS_rebinding) attacks to insecure etcd servers. That is, any website can simply create an authorized DNS name, and direct DNS to `"localhost"` (or any other address). Then, all HTTP endpoints of etcd server listening on `"localhost"` becomes accessible, thus vulnerable to DNS rebinding attacks. See [CVE-2018-5702](https://bugs.chromium.org/p/project-zero/issues/detail?id=1447#c2) for more detail.
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