Merge #15775: [0.18] Doc Backports

bf32bc4b3d Mention new descriptor RPCs in descriptors.md (Pieter Wuille)
1b0752a265 Mention new PSBT RPCs in psbt.md (Pieter Wuille)
956c0aac28 doc: correct bitcoinconsensus_version in shared-libraries (fanquake)
538fef6625 Update bips.md for 0.18.0 (Pieter Wuille)

Pull request description:

  Can be bumped to 0.18.1 if `rc3` ends up being final.

ACKs for commit bf32bc:
  MarcoFalke:
    ACK bf32bc4b3de51d073d9308bdce8db0e0fb083727

Tree-SHA512: 60ad8f0ca53b9fbf6f2a4941bd10971cfece192032d1feff3b25e1b8572caf72cd63c5b8507c376a8bdfb57da6551ac9c2c32dc1f8dc2658a3ea4abf75b0fd9a

4 files changed, 29 insertions, 12 deletions

diff --git a/doc/bips.md b/doc/bips.md
index 76edc94c29..eb24ce6f66 100644
--- a/doc/bips.md
+++ b/doc/bips.md
@@ -1,4 +1,4 @@
-BIPs that are implemented by Bitcoin Core (up-to-date up to **v0.17.0**):
+BIPs that are implemented by Bitcoin Core (up-to-date up to **v0.18.0**):
 
 * [`BIP 9`](https://github.com/bitcoin/bips/blob/master/bip-0009.mediawiki): The changes allowing multiple soft-forks to be deployed in parallel have been implemented since **v0.12.1**  ([PR #7575](https://github.com/bitcoin/bitcoin/pull/7575))
 * [`BIP 11`](https://github.com/bitcoin/bips/blob/master/bip-0011.mediawiki): Multisig outputs are standard since **v0.6.0** ([PR #669](https://github.com/bitcoin/bitcoin/pull/669)).
@@ -15,11 +15,11 @@ BIPs that are implemented by Bitcoin Core (up-to-date up to **v0.17.0**):
 * [`BIP 35`](https://github.com/bitcoin/bips/blob/master/bip-0035.mediawiki): The 'mempool' protocol message (and the protocol version bump to 60002) has been implemented since **v0.7.0** ([PR #1641](https://github.com/bitcoin/bitcoin/pull/1641)).
 * [`BIP 37`](https://github.com/bitcoin/bips/blob/master/bip-0037.mediawiki): The bloom filtering for transaction relaying, partial Merkle trees for blocks, and the protocol version bump to 70001 (enabling low-bandwidth SPV clients) has been implemented since **v0.8.0** ([PR #1795](https://github.com/bitcoin/bitcoin/pull/1795)).
 * [`BIP 42`](https://github.com/bitcoin/bips/blob/master/bip-0042.mediawiki): The bug that would have caused the subsidy schedule to resume after block 13440000 was fixed in **v0.9.2** ([PR #3842](https://github.com/bitcoin/bitcoin/pull/3842)).
-* [`BIP 61`](https://github.com/bitcoin/bips/blob/master/bip-0061.mediawiki): The 'reject' protocol message (and the protocol version bump to 70002) was added in **v0.9.0** ([PR #3185](https://github.com/bitcoin/bitcoin/pull/3185)). Starting *v0.17.0*, whether to send reject messages can be configured with the `-enablebip61` option.
+* [`BIP 61`](https://github.com/bitcoin/bips/blob/master/bip-0061.mediawiki): The 'reject' protocol message (and the protocol version bump to 70002) was added in **v0.9.0** ([PR #3185](https://github.com/bitcoin/bitcoin/pull/3185)). Starting **v0.17.0**, whether to send reject messages can be configured with the `-enablebip61` option, and support is deprecated as of **v0.18.0**.
 * [`BIP 65`](https://github.com/bitcoin/bips/blob/master/bip-0065.mediawiki): The CHECKLOCKTIMEVERIFY softfork was merged in **v0.12.0** ([PR #6351](https://github.com/bitcoin/bitcoin/pull/6351)), and backported to **v0.11.2** and **v0.10.4**. Mempool-only CLTV was added in [PR #6124](https://github.com/bitcoin/bitcoin/pull/6124).
 * [`BIP 66`](https://github.com/bitcoin/bips/blob/master/bip-0066.mediawiki): The strict DER rules and associated version 3 blocks have been implemented since **v0.10.0** ([PR #5713](https://github.com/bitcoin/bitcoin/pull/5713)).
 * [`BIP 68`](https://github.com/bitcoin/bips/blob/master/bip-0068.mediawiki): Sequence locks have been implemented as of **v0.12.1**  ([PR #7184](https://github.com/bitcoin/bitcoin/pull/7184)), and have been activated since *block 419328*.
-* [`BIP 70`](https://github.com/bitcoin/bips/blob/master/bip-0070.mediawiki) [`71`](https://github.com/bitcoin/bips/blob/master/bip-0071.mediawiki) [`72`](https://github.com/bitcoin/bips/blob/master/bip-0072.mediawiki): Payment Protocol support has been available in Bitcoin Core GUI since **v0.9.0** ([PR #5216](https://github.com/bitcoin/bitcoin/pull/5216)).
+* [`BIP 70`](https://github.com/bitcoin/bips/blob/master/bip-0070.mediawiki) [`71`](https://github.com/bitcoin/bips/blob/master/bip-0071.mediawiki) [`72`](https://github.com/bitcoin/bips/blob/master/bip-0072.mediawiki): Payment Protocol support has been available in Bitcoin Core GUI since **v0.9.0** ([PR #5216](https://github.com/bitcoin/bitcoin/pull/5216)). Support can be optionally disabled at build time since **v0.18.0** ([PR 14451](https://github.com/bitcoin/bitcoin/pull/14451)).
 * [`BIP 90`](https://github.com/bitcoin/bips/blob/master/bip-0090.mediawiki): Trigger mechanism for activation of BIPs 34, 65, and 66 has been simplified to block height checks since **v0.14.0** ([PR #8391](https://github.com/bitcoin/bitcoin/pull/8391)).
 * [`BIP 111`](https://github.com/bitcoin/bips/blob/master/bip-0111.mediawiki): `NODE_BLOOM` service bit added, and enforced for all peer versions as of **v0.13.0** ([PR #6579](https://github.com/bitcoin/bitcoin/pull/6579) and [PR #6641](https://github.com/bitcoin/bitcoin/pull/6641)).
 * [`BIP 112`](https://github.com/bitcoin/bips/blob/master/bip-0112.mediawiki): The CHECKSEQUENCEVERIFY opcode has been implemented since **v0.12.1** ([PR #7524](https://github.com/bitcoin/bitcoin/pull/7524)) and has been activated since *block 419328*.
@@ -33,7 +33,7 @@ BIPs that are implemented by Bitcoin Core (up-to-date up to **v0.17.0**):
 * [`BIP 145`](https://github.com/bitcoin/bips/blob/master/bip-0145.mediawiki): getblocktemplate updates for Segregated Witness as of **v0.13.0** ([PR 8149](https://github.com/bitcoin/bitcoin/pull/8149)).
 * [`BIP 147`](https://github.com/bitcoin/bips/blob/master/bip-0147.mediawiki): NULLDUMMY softfork as of **v0.13.1** ([PR 8636](https://github.com/bitcoin/bitcoin/pull/8636) and [PR 8937](https://github.com/bitcoin/bitcoin/pull/8937)).
 * [`BIP 152`](https://github.com/bitcoin/bips/blob/master/bip-0152.mediawiki): Compact block transfer and related optimizations are used as of **v0.13.0** ([PR 8068](https://github.com/bitcoin/bitcoin/pull/8068)).
-* [`BIP 159`](https://github.com/bitcoin/bips/blob/master/bip-0159.mediawiki): NODE_NETWORK_LIMITED service bit [signaling only] is supported as of **v0.16.0** ([PR 11740](https://github.com/bitcoin/bitcoin/pull/11740)).
+* [`BIP 159`](https://github.com/bitcoin/bips/blob/master/bip-0159.mediawiki): The NODE_NETWORK_LIMITED service bit is signalled as of **v0.16.0** ([PR 11740](https://github.com/bitcoin/bitcoin/pull/11740)), and such nodes are connected to as of **v0.17.0** ([PR 10387](https://github.com/bitcoin/bitcoin/pull/10387)).
 * [`BIP 173`](https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki): Bech32 addresses for native Segregated Witness outputs are supported as of **v0.16.0** ([PR 11167](https://github.com/bitcoin/bitcoin/pull/11167)).
 * [`BIP 174`](https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki): RPCs to operate on Partially Signed Bitcoin Transactions (PSBT) are present as of **v0.17.0** ([PR 13557](https://github.com/bitcoin/bitcoin/pull/13557)).
 * [`BIP 176`](https://github.com/bitcoin/bips/blob/master/bip-0176.mediawiki): Bits Denomination [QT only] is supported as of **v0.16.0** ([PR 12035](https://github.com/bitcoin/bitcoin/pull/12035)).
diff --git a/doc/descriptors.md b/doc/descriptors.md
index 5dbcd95e1d..dbdac2c5b6 100644
--- a/doc/descriptors.md
+++ b/doc/descriptors.md
@@ -1,11 +1,18 @@
 # Support for Output Descriptors in Bitcoin Core
 
-Since Bitcoin Core v0.17, there is support for Output Descriptors in the
-`scantxoutset` RPC call. This is a simple language which can be used to
-describe collections of output scripts.
-
-This document describes the language. For the specifics on usage for scanning
-the UTXO set, see the `scantxoutset` RPC help.
+Since Bitcoin Core v0.17, there is support for Output Descriptors. This is a
+simple language which can be used to describe collections of output scripts.
+Supporting RPCs are:
+- `scantxoutset` takes as input descriptors to scan for, and also reports
+  specialized descriptors for the matching UTXOs.
+- `getdescriptorinfo` analyzes a descriptor, and reports a canonicalized version
+  with checksum added.
+- `deriveaddresses` takes as input a descriptor and computes the corresponding
+  addresses.
+- `listunspent` outputs a specialized descriptor for the reported unspent outputs.
+
+This document describes the language. For the specifics on usage, see the RPC
+documentation for the functions mentioned above.
 
 ## Features
 
diff --git a/doc/psbt.md b/doc/psbt.md
index 560b45ef31..9d85af0348 100644
--- a/doc/psbt.md
+++ b/doc/psbt.md
@@ -67,6 +67,9 @@ hardware implementations will typically implement multiple roles simultaneously.
   input a PSBT, adds UTXO, key, and script data to inputs and outputs that miss
   it, and optionally signs inputs. Where possible it also finalizes the partial
   signatures.
+- **`utxoupdatepsbt` (Updater)** is a node RPC that takes a PSBT and updates it
+  to include information available from the UTXO set (works only for SegWit
+  inputs).
 - **`finalizepsbt` (Finalizer, Extractor)** is a utility RPC that finalizes any
   partial signatures, and if all inputs are finalized, converts the result to a
   fully signed transaction which can be broadcast with `sendrawtransaction`.
@@ -74,8 +77,15 @@ hardware implementations will typically implement multiple roles simultaneously.
   can be used at any point in the workflow to merge information added to
   different versions of the same PSBT. In particular it is useful to combine the
   output of multiple Updaters or Signers.
+- **`joinpsbts`** (Creator) is a utility RPC that joins multiple PSBTs together,
+  concatenating the inputs and outputs. This can be used to construct CoinJoin
+  transactions.
 - **`decodepsbt`** is a diagnostic utility RPC which will show all information in
   a PSBT in human-readable form, as well as compute its eventual fee if known.
+- **`analyzepsbt`** is a utility RPC that examines an RPC and reports the
+  next steps in the workflow if known, computes the fee of the resulting
+  transaction, and estimates the weight and feerate if possible.
+
 
 ### Workflows
 
diff --git a/doc/shared-libraries.md b/doc/shared-libraries.md
index dc363582cc..e960863a80 100644
--- a/doc/shared-libraries.md
+++ b/doc/shared-libraries.md
@@ -7,11 +7,11 @@ The purpose of this library is to make the verification functionality that is cr
 
 ### API
 
-The interface is defined in the C header `bitcoinconsensus.h` located in  `src/script/bitcoinconsensus.h`.
+The interface is defined in the C header `bitcoinconsensus.h` located in `src/script/bitcoinconsensus.h`.
 
 #### Version
 
-`bitcoinconsensus_version` returns an `unsigned int` with the API version *(currently at an experimental `0`)*.
+`bitcoinconsensus_version` returns an `unsigned int` with the API version *(currently `1`)*.
 
 #### Script Validation