From: Andre Noll <maan@tuebingen.mpg.de>
Date: Tue, 2 May 2023 19:16:29 +0000 (+0200)
Subject: openssl: Introduce openssl_perror().
X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=6a5b7c55fc65303245e9e54c65ba409da1215343;p=paraslash.git

openssl: Introduce openssl_perror().

Openssl has a decent error reporting framework, but we only employ
it if get_random_bytes_or_die() fails. This patch abstracts out a
new helper which prints the error string of the earliest error code
from the thread's error queue. We make the helper return -E_OPENSSL
unconditionally as this simplifies callers a bit.

Only get_random_bytes_or_die() calls the new helper for now but
additional callers will be added in subsequent commits.
---

diff --git a/error.h b/error.h
index 8805c9c7..899543ab 100644
--- a/error.h
+++ b/error.h
@@ -155,6 +155,7 @@
 	PARA_ERROR(OGG_PACKET_IN, "ogg_stream_packetin() failed"), \
 	PARA_ERROR(OGG_SYNC, "internal ogg storage overflow"), \
 	PARA_ERROR(OPENSSH_PARSE, "could not parse openssh private key"), \
+	PARA_ERROR(OPENSSL, "openssl error"), \
 	PARA_ERROR(OPUS_COMMENT, "invalid or corrupted opus comment"), \
 	PARA_ERROR(OPUS_DECODE, "opus decode error"), \
 	PARA_ERROR(OPUS_HEADER, "invalid opus header"), \
diff --git a/openssl.c b/openssl.c
index e3416949..6dba1b27 100644
--- a/openssl.c
+++ b/openssl.c
@@ -24,15 +24,21 @@ struct asymmetric_key {
 	RSA *rsa;
 };
 
+static int openssl_perror(const char *pfx)
+{
+	unsigned long err = ERR_get_error();
+	PARA_ERROR_LOG("%s: \"%s\"\n", pfx, ERR_reason_error_string(err));
+	return -E_OPENSSL;
+}
+
 void get_random_bytes_or_die(unsigned char *buf, int num)
 {
-	unsigned long err;
+	int ret;
 
-	/* RAND_bytes() returns 1 on success, 0 otherwise. */
-	if (RAND_bytes(buf, num) == 1)
+	if (RAND_bytes(buf, num) == 1) /* success */
 		return;
-	err = ERR_get_error();
-	PARA_EMERG_LOG("%s\n", ERR_reason_error_string(err));
+	ret = openssl_perror("RAND_bytes");
+	PARA_EMERG_LOG("%s\n", strerror(-ret));
 	exit(EXIT_FAILURE);
 }