diff options
Diffstat (limited to 'src/backend/libpq/hba.c')
| -rw-r--r-- | src/backend/libpq/hba.c | 38 |
1 files changed, 28 insertions, 10 deletions
diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c index 332fad27835..fecee8224d0 100644 --- a/src/backend/libpq/hba.c +++ b/src/backend/libpq/hba.c @@ -2873,8 +2873,11 @@ check_ident_usermap(IdentLine *identLine, const char *usermap_name, !token_has_regexp(identLine->pg_user) && (ofs = strstr(identLine->pg_user->string, "\\1")) != NULL) { + const char *repl_str; + size_t repl_len; + char *old_pg_user; char *expanded_pg_user; - int offset; + size_t offset; /* substitution of the first argument requested */ if (matches[1].rm_so < 0) @@ -2886,18 +2889,33 @@ check_ident_usermap(IdentLine *identLine, const char *usermap_name, *error_p = true; return; } + repl_str = system_user + matches[1].rm_so; + repl_len = matches[1].rm_eo - matches[1].rm_so; /* - * length: original length minus length of \1 plus length of match - * plus null terminator + * It's allowed to have more than one \1 in the string, and we'll + * replace them all. But that's pretty unusual so we optimize on + * the assumption of only one occurrence, which motivates doing + * repeated replacements instead of making two passes over the + * string to determine the final length right away. */ - expanded_pg_user = palloc0(strlen(identLine->pg_user->string) - 2 + (matches[1].rm_eo - matches[1].rm_so) + 1); - offset = ofs - identLine->pg_user->string; - memcpy(expanded_pg_user, identLine->pg_user->string, offset); - memcpy(expanded_pg_user + offset, - system_user + matches[1].rm_so, - matches[1].rm_eo - matches[1].rm_so); - strcat(expanded_pg_user, ofs + 2); + old_pg_user = identLine->pg_user->string; + do + { + /* + * length: current length minus length of \1 plus length of + * replacement plus null terminator + */ + expanded_pg_user = palloc(strlen(old_pg_user) - 2 + repl_len + 1); + /* ofs points into the old_pg_user string at this point */ + offset = ofs - old_pg_user; + memcpy(expanded_pg_user, old_pg_user, offset); + memcpy(expanded_pg_user + offset, repl_str, repl_len); + strcpy(expanded_pg_user + offset + repl_len, ofs + 2); + if (old_pg_user != identLine->pg_user->string) + pfree(old_pg_user); + old_pg_user = expanded_pg_user; + } while ((ofs = strstr(old_pg_user + offset + repl_len, "\\1")) != NULL); /* * Mark the token as quoted, so it will only be compared literally |