From 5174da45a3406c389d25d71f9e783427cdf2019e Mon Sep 17 00:00:00 2001 From: "Dr. David von Oheimb" Date: Wed, 9 Oct 2024 22:05:19 +0200 Subject: [PATCH] TRACE: automatically respect disabled categories by fixing OSSL_trace_begin() to return NULL when given category is not enabled Reviewed-by: Tom Cosgrove Reviewed-by: Tomas Mraz (Merged from https://github.com/openssl/openssl/pull/25652) (cherry picked from commit 72d3e9bac41302e5bc00db1bef014b0ca810d2cf) --- crypto/trace.c | 2 +- doc/man3/OSSL_trace_enabled.pod | 8 ++++++-- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/crypto/trace.c b/crypto/trace.c index dc308d819d0..e7a5966f369 100644 --- a/crypto/trace.c +++ b/crypto/trace.c @@ -474,7 +474,7 @@ BIO *OSSL_trace_begin(int category) char *prefix = NULL; category = ossl_trace_get_category(category); - if (category < 0) + if (category < 0 || !OSSL_trace_enabled(category)) return NULL; channel = trace_channels[category].bio; diff --git a/doc/man3/OSSL_trace_enabled.pod b/doc/man3/OSSL_trace_enabled.pod index fcbea3cbf61..ee0e436e69b 100644 --- a/doc/man3/OSSL_trace_enabled.pod +++ b/doc/man3/OSSL_trace_enabled.pod @@ -90,9 +90,10 @@ I is enabled, i.e., if the tracing facility has been statically enabled (see L below) and a trace channel has been registered using L or L. -OSSL_trace_begin() is used to starts a tracing section, and get the -channel for the given I in form of a BIO. +OSSL_trace_begin() is used to start a tracing section, +and get the channel for the given I in form of a BIO. This BIO can only be used for output. +The pointer returned is NULL if the category is invalid or not enabled. OSSL_trace_end() is used to end a tracing section. @@ -189,6 +190,9 @@ expands to =head1 NOTES +It is not needed to guard trace output function calls like +I by I. + If producing the trace output requires carrying out auxiliary calculations, this auxiliary code should be placed inside a conditional block which is executed only if the trace category is enabled. -- 2.47.2