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User-defined routines that use md5 hash for other purposes than generating test data

Query goal: Find user-defined routines that use md5 hashes for the security purposes. Nowadays such hashes can be calculated too quickly and its use should be avoided at least for hashing passwords. Exclude routines that invoke both md5 function and generate_series function and are thus probably used to generate test data.
Notes about the query: Refers to the column pg_proc.prokind and thus works starting from PostgreSQL 11. In the returned body of routine the query replaces each newline character with the line break (br) tag for the better readability in case the query result is displayed in a web browser. There could be multiple routines with the same name but with different parameters in the same schema (overloading). Thus, for the unique identification of the routine it is necessary to present also its parameters in addition to the schema name and routine name.
Query type: Problem detection (Each row in the result could represent a flaw in the design)
Query reliability: Medium (Medium number of false-positive results)
Query license: MIT License
Data source: INFORMATION_SCHEMA+system catalog
SQL query: Click on query to copy it

SELECT 
  pg_namespace.nspname AS routine_schema, 
  pg_proc.proname AS routine_name, 
  pg_get_function_identity_arguments(pg_proc.oid) AS parameters, CASE WHEN pg_proc.prokind='f' THEN 'FUNCTION'
  WHEN pg_proc.prokind='p' THEN 'PROCEDURE'
  WHEN pg_proc.prokind='w' THEN 'WINDOW FUNCTION' END AS routine_type,
  regexp_replace( regexp_replace(pg_get_functiondef(pg_proc.oid),'<','&lt','g'),'[\r\n]','<br>','g')  AS routine_src
FROM 
  pg_catalog.pg_proc, 
  pg_catalog.pg_namespace
WHERE 
  pg_proc.pronamespace = pg_namespace.oid
    AND pg_proc.prokind<>'a'
 AND pg_proc.proname NOT IN ('f_assume_you_must_use_files', 'f_check_format_comma_separated_list', 'f_check_password', 'f_default_value_with_no_match') AND
pg_namespace.nspname NOT IN (SELECT schema_name
FROM INFORMATION_SCHEMA.schemata
WHERE schema_name<>'public' AND
schema_owner='postgres' AND schema_name IS NOT NULL) 
AND (pg_get_functiondef(pg_proc.oid) ~* 'crypt[(].+, gen_salt[(]''md5'
OR (pg_get_functiondef(pg_proc.oid) ~* 'md5[[:space:]]*[(]' 
AND pg_get_functiondef(pg_proc.oid) !~* 'generate_series'))
ORDER BY routine_schema, routine_name, parameters;

Collections where the query belongs to

Collection nameCollection description
Find problems automaticallyQueries, that results point to problems in the database. Each query in the collection produces an initial assessment. However, a human reviewer has the final say as to whether there is a problem or not .

Categories where the query belongs to

Category nameCategory description
Does not work in some earlier PostgreSQL versionQueries of this category provide information that was not available in some earlier PostgreSQL version
SecurityQueries of this category provide information about the security measures.

Reference materials for further reading

Reference
https://crypto.stackexchange.com/questions/70036/is-there-really-no-use-for-md5-anymore
https://stackoverflow.com/questions/30496061/why-not-use-md5-for-password-hashing

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