commit fe329cea3fdcda1865c21e24b5fa3e5aef219eaa
author Valerio Setti <valerio.setti@nordicsemi.no> Tue Feb 06 08:00:18 2024 +0100
committer Valerio Setti <valerio.setti@nordicsemi.no> Tue Feb 06 08:00:18 2024 +0100
tree 16173bc8d87ba3bda30da67f60c681d1f5495411
parent 45c33ed41ec2d89535aed1ac81d4345939e5c42a

rsa: handle buffer length similarly in private and public key parsing

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>

library/rsa.c

diff --git a/library/rsa.c b/library/rsa.c
index f4add91..b250e1d 100644
--- a/library/rsa.c
+++ b/library/rsa.c
@@ -109,6 +109,10 @@
 
     end = p + len;
 
+    if (end > (key + keylen)) {
+        return MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
+    }
+
     if ((ret = mbedtls_asn1_get_int(&p, end, &version)) != 0) {
         return ret;
     }
@@ -239,7 +243,9 @@
         return ret;
     }
 
-    if (p + len != end) {
+    end = p + len;
+
+    if (end > (key + keylen)) {
         return MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
     }
 

tests/suites/test_suite_rsa.data

diff --git a/tests/suites/test_suite_rsa.data b/tests/suites/test_suite_rsa.data
index b404f00..b89d158 100644
--- a/tests/suites/test_suite_rsa.data
+++ b/tests/suites/test_suite_rsa.data
@@ -707,7 +707,7 @@
 rsa_parse_pkcs1_key:1:"308189028181009f091e6968b474f76f0e9c237c1d895996ae704b4f6d706acec8d2daac6209bf524aa3f658d0283adba1077f6cbe92e425dcde52290b239cade91be86c88425434986806e85734e159768f3dfea932baaa9409d25bace8ee9dce0cdde0903207299de575ae60feccf0daf82334ab83638539b0da74072f253acea8afc8e66bb70203000000":MBEDTLS_ERR_RSA_BAD_INPUT_DATA
 
 RSA parse public key - wrong sequence length
-rsa_parse_pkcs1_key:1:"308188028181009f091e6968b474f76f0e9c237c1d895996ae704b4f6d706acec8d2daac6209bf524aa3f658d0283adba1077f6cbe92e425dcde52290b239cade91be86c88425434986806e85734e159768f3dfea932baaa9409d25bace8ee9dce0cdde0903207299de575ae60feccf0daf82334ab83638539b0da74072f253acea8afc8e66bb70203010001":MBEDTLS_ERR_ASN1_LENGTH_MISMATCH
+rsa_parse_pkcs1_key:1:"308188028181009f091e6968b474f76f0e9c237c1d895996ae704b4f6d706acec8d2daac6209bf524aa3f658d0283adba1077f6cbe92e425dcde52290b239cade91be86c88425434986806e85734e159768f3dfea932baaa9409d25bace8ee9dce0cdde0903207299de575ae60feccf0daf82334ab83638539b0da74072f253acea8afc8e66bb70203010001":MBEDTLS_ERR_ASN1_OUT_OF_DATA
 
 RSA parse public key - wrong modulus length
 rsa_parse_pkcs1_key:1:"308189028180009f091e6968b474f76f0e9c237c1d895996ae704b4f6d706acec8d2daac6209bf524aa3f658d0283adba1077f6cbe92e425dcde52290b239cade91be86c88425434986806e85734e159768f3dfea932baaa9409d25bace8ee9dce0cdde0903207299de575ae60feccf0daf82334ab83638539b0da74072f253acea8afc8e66bb70203010001":MBEDTLS_ERR_ASN1_UNEXPECTED_TAG

tests/suites/test_suite_x509parse.data

diff --git a/tests/suites/test_suite_x509parse.data b/tests/suites/test_suite_x509parse.data
index 261c220..b9ae20c 100644
--- a/tests/suites/test_suite_x509parse.data
+++ b/tests/suites/test_suite_x509parse.data
@@ -1774,7 +1774,7 @@
 
 X509 CRT ASN1 (TBS, inv SubPubKeyInfo, inv internal bitstring length)
 depends_on:MBEDTLS_RSA_C:MBEDTLS_MD_CAN_SHA256
-x509parse_crt:"308180306ba0030201008204deadbeef300d06092a864886f70d01010b0500300c310a30080600130454657374301c170c303930313031303030303030170c303931323331323335393539300c310a300806001304546573743015300d06092A864886F70D0101010500030400300000300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_PK_INVALID_PUBKEY + MBEDTLS_ERR_ASN1_LENGTH_MISMATCH
+x509parse_crt:"308180306ba0030201008204deadbeef300d06092a864886f70d01010b0500300c310a30080600130454657374301c170c303930313031303030303030170c303931323331323335393539300c310a300806001304546573743015300d06092A864886F70D0101010500030400300000300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_PK_INVALID_PUBKEY + MBEDTLS_ERR_ASN1_OUT_OF_DATA
 
 X509 CRT ASN1 (TBS, inv SubPubKeyInfo, inv internal bitstring tag)
 depends_on:MBEDTLS_RSA_C:MBEDTLS_MD_CAN_SHA256