From cfdd1d9be89ae4b1e9d654ff84512671ff73bc2c Mon Sep 17 00:00:00 2001
From: Andrey Volk <andywolk@gmail.com>
Date: Tue, 26 Jan 2021 20:26:14 +0300
Subject: [PATCH] [mod_http_cache] Handle error cases to avoid using
uninitialized variables in aws logic.
---
src/mod/applications/mod_http_cache/aws.c | 27 +++++++++++++----------
1 file changed, 15 insertions(+), 12 deletions(-)
diff --git a/src/mod/applications/mod_http_cache/aws.c b/src/mod/applications/mod_http_cache/aws.c
index 740fe2e9c4..cc02b4e5b5 100644
--- a/src/mod/applications/mod_http_cache/aws.c
+++ b/src/mod/applications/mod_http_cache/aws.c
@@ -144,10 +144,12 @@ static char* aws_s3_signature_key(char* key_signing, switch_aws_s3_profile* aws_
char key_service[SHA256_DIGEST_LENGTH];
char* aws4_secret_access_key = switch_mprintf("AWS4%s", aws_s3_profile->access_key_secret);
- hmac256(key_date, SHA256_DIGEST_LENGTH, aws4_secret_access_key, strlen(aws4_secret_access_key), aws_s3_profile->date_stamp);
- hmac256(key_region, SHA256_DIGEST_LENGTH, key_date, SHA256_DIGEST_LENGTH, aws_s3_profile->region);
- hmac256(key_service, SHA256_DIGEST_LENGTH, key_region, SHA256_DIGEST_LENGTH, "s3");
- hmac256(key_signing, SHA256_DIGEST_LENGTH, key_service, SHA256_DIGEST_LENGTH, "aws4_request");
+ if (!hmac256(key_date, SHA256_DIGEST_LENGTH, aws4_secret_access_key, (unsigned int)strlen(aws4_secret_access_key), aws_s3_profile->date_stamp)
+ || !hmac256(key_region, SHA256_DIGEST_LENGTH, key_date, SHA256_DIGEST_LENGTH, aws_s3_profile->region)
+ || !hmac256(key_service, SHA256_DIGEST_LENGTH, key_region, SHA256_DIGEST_LENGTH, "s3")
+ || !hmac256(key_signing, SHA256_DIGEST_LENGTH, key_service, SHA256_DIGEST_LENGTH, "aws4_request")) {
+ key_signing = NULL;
+ }
switch_safe_free(aws4_secret_access_key);
@@ -166,7 +168,7 @@ static char* aws_s3_standardized_query_string(switch_aws_s3_profile* aws_s3_prof
char* standardized_query_string;
credential = switch_mprintf("%s%%2F%s%%2F%s%%2Fs3%%2Faws4_request", aws_s3_profile->access_key_id, aws_s3_profile->date_stamp, aws_s3_profile->region);
- switch_snprintf(expires, 9, "%ld", aws_s3_profile->expires);
+ switch_snprintf(expires, 9, "%" SWITCH_TIME_T_FMT, aws_s3_profile->expires);
standardized_query_string = switch_mprintf(
"X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=%s&X-Amz-Date=%s&X-Amz-Expires=%s&X-Amz-SignedHeaders=host",
@@ -243,13 +245,14 @@ static char *aws_s3_authentication_create(switch_aws_s3_profile* aws_s3_profile)
string_to_sign = aws_s3_string_to_sign(standardized_request, aws_s3_profile);
// Get signature_key
- aws_s3_signature_key(signature_key, aws_s3_profile);
-
- // Get signature
- hmac256_hex(signature, signature_key, SHA256_DIGEST_LENGTH, string_to_sign);
-
- // Build final query string
- query_param = switch_mprintf("%s&X-Amz-Signature=%s", standardized_query_string, signature);
+ if (!aws_s3_signature_key(signature_key, aws_s3_profile)
+ // Get signature
+ || !hmac256_hex(signature, signature_key, SHA256_DIGEST_LENGTH, string_to_sign)) {
+ query_param = NULL;
+ } else {
+ // Build final query string
+ query_param = switch_mprintf("%s&X-Amz-Signature=%s", standardized_query_string, signature);
+ }
switch_safe_free(string_to_sign);
switch_safe_free(standardized_query_string);