diff options
| -rw-r--r-- | CHANGES | 37 | ||||
| -rw-r--r-- | crypto/asn1/a_verify.c | 12 | ||||
| -rw-r--r-- | crypto/dsa/dsa_asn1.c | 14 | ||||
| -rw-r--r-- | crypto/ecdsa/ecs_vrf.c | 15 | ||||
| -rw-r--r-- | crypto/x509/x_all.c | 2 |
5 files changed, 78 insertions, 2 deletions
@@ -4,6 +4,43 @@ Changes between 1.0.1j and 1.0.1k [xx XXX xxxx] + *) Fix various certificate fingerprint issues. + + By using non-DER or invalid encodings outside the signed portion of a + certificate the fingerprint can be changed without breaking the signature. + Although no details of the signed portion of the certificate can be changed + this can cause problems with some applications: e.g. those using the + certificate fingerprint for blacklists. + + 1. Reject signatures with non zero unused bits. + + If the BIT STRING containing the signature has non zero unused bits reject + the signature. All current signature algorithms require zero unused bits. + + 2. Check certificate algorithm consistency. + + Check the AlgorithmIdentifier inside TBS matches the one in the + certificate signature. NB: this will result in signature failure + errors for some broken certificates. + + Thanks to Konrad Kraszewski from Google for reporting this issue. + + 3. Check DSA/ECDSA signatures use DER. + + Reencode DSA/ECDSA signatures and compare with the original received + signature. Return an error if there is a mismatch. + + This will reject various cases including garbage after signature + (thanks to Antti Karjalainen and Tuomo Untinen from the Codenomicon CROSS + program for discovering this case) and use of BER or invalid ASN.1 INTEGERs + (negative or with leading zeroes). + + Further analysis was conducted and fixes were developed by Stephen Henson + of the OpenSSL core team. + + (CVE-2014-8275) + [Steve Henson] + *) Do not resume sessions on the server if the negotiated protocol version does not match the session's version. Resuming with a different version, while not strictly forbidden by the RFC, is of questionable diff --git a/crypto/asn1/a_verify.c b/crypto/asn1/a_verify.c index fc84cd3d19..a571009ab9 100644 --- a/crypto/asn1/a_verify.c +++ b/crypto/asn1/a_verify.c @@ -90,6 +90,12 @@ int ASN1_verify(i2d_of_void *i2d, X509_ALGOR *a, ASN1_BIT_STRING *signature, ASN1err(ASN1_F_ASN1_VERIFY,ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM); goto err; } + + if (signature->type == V_ASN1_BIT_STRING && signature->flags & 0x7) + { + ASN1err(ASN1_F_ASN1_VERIFY, ASN1_R_INVALID_BIT_STRING_BITS_LEFT); + goto err; + } inl=i2d(data,NULL); buf_in=OPENSSL_malloc((unsigned int)inl); @@ -146,6 +152,12 @@ int ASN1_item_verify(const ASN1_ITEM *it, X509_ALGOR *a, return -1; } + if (signature->type == V_ASN1_BIT_STRING && signature->flags & 0x7) + { + ASN1err(ASN1_F_ASN1_VERIFY, ASN1_R_INVALID_BIT_STRING_BITS_LEFT); + return -1; + } + EVP_MD_CTX_init(&ctx); /* Convert signature OID into digest and public key OIDs */ diff --git a/crypto/dsa/dsa_asn1.c b/crypto/dsa/dsa_asn1.c index 6058534374..473af873e0 100644 --- a/crypto/dsa/dsa_asn1.c +++ b/crypto/dsa/dsa_asn1.c @@ -176,13 +176,25 @@ int DSA_verify(int type, const unsigned char *dgst, int dgst_len, const unsigned char *sigbuf, int siglen, DSA *dsa) { DSA_SIG *s; + const unsigned char *p = sigbuf; + unsigned char *der = NULL; + int derlen = -1; int ret=-1; s = DSA_SIG_new(); if (s == NULL) return(ret); - if (d2i_DSA_SIG(&s,&sigbuf,siglen) == NULL) goto err; + if (d2i_DSA_SIG(&s,&p,siglen) == NULL) goto err; + /* Ensure signature uses DER and doesn't have trailing garbage */ + derlen = i2d_DSA_SIG(s, &der); + if (derlen != siglen || memcmp(sigbuf, der, derlen)) + goto err; ret=DSA_do_verify(dgst,dgst_len,s,dsa); err: + if (derlen > 0) + { + OPENSSL_cleanse(der, derlen); + OPENSSL_free(der); + } DSA_SIG_free(s); return(ret); } diff --git a/crypto/ecdsa/ecs_vrf.c b/crypto/ecdsa/ecs_vrf.c index ef9acf7b61..2836efe5ef 100644 --- a/crypto/ecdsa/ecs_vrf.c +++ b/crypto/ecdsa/ecs_vrf.c @@ -57,6 +57,7 @@ */ #include "ecs_locl.h" +#include "cryptlib.h" #ifndef OPENSSL_NO_ENGINE #include <openssl/engine.h> #endif @@ -84,13 +85,25 @@ int ECDSA_verify(int type, const unsigned char *dgst, int dgst_len, const unsigned char *sigbuf, int sig_len, EC_KEY *eckey) { ECDSA_SIG *s; + const unsigned char *p = sigbuf; + unsigned char *der = NULL; + int derlen = -1; int ret=-1; s = ECDSA_SIG_new(); if (s == NULL) return(ret); - if (d2i_ECDSA_SIG(&s, &sigbuf, sig_len) == NULL) goto err; + if (d2i_ECDSA_SIG(&s, &p, sig_len) == NULL) goto err; + /* Ensure signature uses DER and doesn't have trailing garbage */ + derlen = i2d_ECDSA_SIG(s, &der); + if (derlen != sig_len || memcmp(sigbuf, der, derlen)) + goto err; ret=ECDSA_do_verify(dgst, dgst_len, s, eckey); err: + if (derlen > 0) + { + OPENSSL_cleanse(der, derlen); + OPENSSL_free(der); + } ECDSA_SIG_free(s); return(ret); } diff --git a/crypto/x509/x_all.c b/crypto/x509/x_all.c index e06602d65a..fef55f89d9 100644 --- a/crypto/x509/x_all.c +++ b/crypto/x509/x_all.c @@ -72,6 +72,8 @@ int X509_verify(X509 *a, EVP_PKEY *r) { + if (X509_ALGOR_cmp(a->sig_alg, a->cert_info->signature)) + return 0; return(ASN1_item_verify(ASN1_ITEM_rptr(X509_CINF),a->sig_alg, a->signature,a->cert_info,r)); } |