Correctly treat NULL in the parameters of a SubjectPublicKeyInfo

sjaeckel · sjaeckel · commit 35b0fc20d3ec · 2025-10-03T15:33:24.000+02:00
The NULL is optional.

Signed-off-by: Steffen Jaeckel &lt;s@jaeckel.eu&gt;
diff --git a/src/pk/asn1/x509/x509_decode_subject_public_key_info.c b/src/pk/asn1/x509/x509_decode_subject_public_key_info.c
@@ -75,6 +75,8 @@ int x509_decode_subject_public_key_info(const unsigned char *in, unsigned long i
       alg_id_num = 1;
    } else {
       LTC_SET_ASN1(alg_id, 1, parameters_type, parameters, *_parameters_len);
+      if (parameters_type == LTC_ASN1_NULL)
+         alg_id[1].optional = 1;
       alg_id_num = 2;
    }
 

Original file line number	Diff line number	Diff line change
`@@ -75,6 +75,8 @@ int x509_decode_subject_public_key_info(const unsigned char *in, unsigned long i`
`75`	`75`	`alg_id_num = 1;`
`76`	`76`	`} else {`
`77`	`77`	`LTC_SET_ASN1(alg_id, 1, parameters_type, parameters, *_parameters_len);`
	`78`	`+ if (parameters_type == LTC_ASN1_NULL)`
	`79`	`+ alg_id[1].optional = 1;`
`78`	`80`	`alg_id_num = 2;`
`79`	`81`	`}`
`80`	`82`