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AuthenticationSASL
AuthenticationSASL is a backend protocol message. Identifies the message as an authentication request.
Reading PostgreSQL 18.6.
Description
AuthenticationSASL is a backend protocol message. Identifies the message as an authentication request.
- Direction
- Backend → frontend
- First wire field
- Byte1('R')
- Field entries
- 4
- Documented flow contexts
- Start-up
Usage
AuthenticationSASL (B)Framing and repetition
The complete definition below retains repetition, counts and conditional fields. A numbered table row is a documented field definition, not a fixed byte offset. Integer encodings and flow rules follow the same-version protocol chapter.
Wire fields in documented order
| Position | Format | Meaning |
|---|---|---|
| 1 | Byte1('R') | Identifies the message as an authentication request. |
| 2 | Int32 | Length of message contents in bytes, including self. |
| 3 | Int32(10) | Specifies that SASL authentication is required. |
| 4 | String | Name of a SASL authentication mechanism. |
Manual definition
-
- Byte1('R')
-
Identifies the message as an authentication request.
- Int32
-
Length of message contents in bytes, including self.
- Int32(10)
-
Specifies that SASL authentication is required.
The message body is a list of SASL authentication mechanisms, in the server's order of preference. A zero byte is required as terminator after the last authentication mechanism name. For each mechanism, there is the following:
- String
-
Name of a SASL authentication mechanism.
Related entries
Documentation and source
Source build
- Version
- 18.6
- Build
- https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2
- Source fingerprint
555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f
Compare versions
PostgreSQL 17 → 18: unchanged.
Compares recorded interfaces and attributes. Source fingerprints and build metadata are excluded; an absent sample is not proof of the introduction or removal release.
Related entries
Export JSON · Back to Protocol Messages · Recorded in PostgreSQL 10 through 20; the first sample is not necessarily its introduction.