From e75ae70ef1a152dac9a066506cafd2bbf7b2565e Mon Sep 17 00:00:00 2001

Message-Id: <e75ae70ef1a152dac9a066506cafd2bbf7b2565e.1681989428.git.pmatilai@redhat.com>

From: "Neal H. Walfield" <neal@pep.foundation>

Date: Wed, 12 Apr 2023 17:56:19 +0200

Subject: [PATCH] Add pgpVerifySignature2() and pgpPrtParams2()

Add new functions pgpVerifySignature2() and pgpPrtParams2(), which are

like their earlier versions, but optionally return descriptive error

messages (in the case of failure) or lints (in the case of success).

Adjust tests accordingly.

This requires rpm-sequoia 1.4 or later.

See https://github.com/rpm-software-management/rpm-sequoia/issues/39

and

https://github.com/rpm-software-management/rpm/issues/2127#issuecomment-1482646398

Fixes #2483.

This is a backport of commit 87b9e0c28c3df3937f6676ee1b4164d6154dd9d3

---

 configure.ac            |  2 +-

 include/rpm/rpmpgp.h    | 23 +++++++++++++++++++++++

 lib/rpmvs.c             | 19 ++++++++++++++++---

 rpmio/rpmkeyring.c      |  7 ++++++-

 rpmio/rpmpgp_internal.c | 15 +++++++++++++++

 rpmio/rpmpgp_sequoia.c  |  7 +++++++

 tests/rpmi.at           | 10 ++++++++--

 tests/rpmsigdig.at      | 20 +++++++++++++++++---

 9 files changed, 95 insertions(+), 10 deletions(-)

diff --git a/configure.ac b/configure.ac

index e6676c581..1d173e4e2 100644

--- a/configure.ac

+++ b/configure.ac

@@ -384,7 +384,7 @@ AC_SUBST(WITH_LIBGCRYPT_LIB)

 WITH_RPM_SEQUOIA_INCLUDE=

 WITH_RPM_SEQUOIA_LIB=

 if test "$with_crypto" = sequoia ; then

-  PKG_CHECK_MODULES([RPM_SEQUOIA], [rpm-sequoia], [have_rpm_sequoia=yes], [have_rpm_sequoia=no])

+  PKG_CHECK_MODULES([RPM_SEQUOIA], [rpm-sequoia >= 1.4.0], [have_rpm_sequoia=yes], [have_rpm_sequoia=no])

   if test "$have_rpm_sequoia" = "yes"; then

      WITH_RPM_SEQUOIA_INCLUDE="$RPM_SEQUOIA_CFLAGS"

      WITH_RPM_SEQUOIA_LIB="$RPM_SEQUOIA_LIBS"

diff --git a/include/rpm/rpmpgp.h b/include/rpm/rpmpgp.h

index a3238a643..3352129b8 100644

--- a/include/rpm/rpmpgp.h

+++ b/include/rpm/rpmpgp.h

@@ -1013,6 +1013,18 @@ int pgpPubkeyKeyID(const uint8_t * pkt, size_t pktlen, pgpKeyID_t keyid);

 int pgpPrtParams(const uint8_t *pkts, size_t pktlen, unsigned int pkttype,

 		 pgpDigParams * ret);

+/** \ingroup rpmpgp

+ * Parse a OpenPGP packet(s).

+ * @param pkts		OpenPGP packet(s)

+ * @param pktlen	OpenPGP packet(s) length (no. of bytes)

+ * @param pkttype	Expected packet type (signature/key) or 0 for any

+ * @param[out] ret	signature/pubkey packet parameters on success (alloced)

+ * @param[out] lints	error messages and lints

+ * @return		-1 on error, 0 on success

+ */

+int pgpPrtParams2(const uint8_t *pkts, size_t pktlen, unsigned int pkttype,

+		 pgpDigParams * ret, char **lints);

+

 /** \ingroup rpmpgp

  * Parse subkey parameters from OpenPGP packet(s).

  * @param pkts		OpenPGP packet(s)

@@ -1191,6 +1203,17 @@ const uint8_t *pgpDigParamsSignID(pgpDigParams digp);

  */

 const char *pgpDigParamsUserID(pgpDigParams digp);

+/** \ingroup rpmpgp

+ * Verify a PGP signature and return a error message or lint.

+ * @param key		public key

+ * @param sig		signature

+ * @param hashctx	digest context

+ * @param lints	error messages and lints

+ * @return 		RPMRC_OK on success

+ */

+rpmRC pgpVerifySignature2(pgpDigParams key, pgpDigParams sig, DIGEST_CTX hashctx,

+                          char **lints);

+

 /** \ingroup rpmpgp

  * Retrieve the object's version.

  *

diff --git a/lib/rpmvs.c b/lib/rpmvs.c

index a1425ea17..9b2106927 100644

--- a/lib/rpmvs.c

+++ b/lib/rpmvs.c

@@ -193,10 +193,23 @@ static void rpmsinfoInit(const struct vfyinfo_s *vinfo,

     }

     if (sinfo->type == RPMSIG_SIGNATURE_TYPE) {

-	if (pgpPrtParams(data, dlen, PGPTAG_SIGNATURE, &sinfo->sig)) {

-	    rasprintf(&sinfo->msg, _("%s tag %u: invalid OpenPGP signature"),

-		    origin, td->tag);

+	char *lints = NULL;

+        int ec = pgpPrtParams2(data, dlen, PGPTAG_SIGNATURE, &sinfo->sig, &lints);

+	if (ec) {

+	    if (lints) {

+		rasprintf(&sinfo->msg,

+			("%s tag %u: invalid OpenPGP signature: %s"),

+			origin, td->tag, lints);

+		free(lints);

+	    } else {

+		rasprintf(&sinfo->msg,

+			_("%s tag %u: invalid OpenPGP signature"),

+			origin, td->tag);

+	    }

 	    goto exit;

+	} else if (lints) {

+	    rpmlog(RPMLOG_WARNING, "%s\n", lints);

+	    free(lints);

 	}

 	sinfo->hashalgo = pgpDigParamsAlgo(sinfo->sig, PGPVAL_HASHALGO);

 	sinfo->keyid = pgpGrab(pgpDigParamsSignID(sinfo->sig)+4, 4);

diff --git a/rpmio/rpmkeyring.c b/rpmio/rpmkeyring.c

index db72892d9..712004bc8 100644

--- a/rpmio/rpmkeyring.c

+++ b/rpmio/rpmkeyring.c

@@ -328,7 +328,12 @@ rpmRC rpmKeyringVerifySig(rpmKeyring keyring, pgpDigParams sig, DIGEST_CTX ctx)

 	    pgpkey = key->pgpkey;

 	/* We call verify even if key not found for a signature sanity check */

-	rc = pgpVerifySignature(pgpkey, sig, ctx);

+	char *lints = NULL;

+	rc = pgpVerifySignature2(pgpkey, sig, ctx, &lints);

+	if (lints) {

+	    rpmlog(rc ? RPMLOG_ERR : RPMLOG_WARNING, "%s\n", lints);

+	    free(lints);

+	}

     }

     if (keyring)

diff --git a/rpmio/rpmpgp_internal.c b/rpmio/rpmpgp_internal.c

index 0fcd220e4..a049c09b2 100644

--- a/rpmio/rpmpgp_internal.c

+++ b/rpmio/rpmpgp_internal.c

@@ -1095,6 +1095,14 @@ int pgpPrtParams(const uint8_t * pkts, size_t pktlen, unsigned int pkttype,

     return rc;

 }

+int pgpPrtParams2(const uint8_t * pkts, size_t pktlen, unsigned int pkttype,

+                  pgpDigParams * ret, char **lints)

+{

+    if (lints)

+        *lints = NULL;

+    return pgpPrtParams(pkts, pktlen, pkttype, ret);

+}

+

 int pgpPrtParamsSubkeys(const uint8_t *pkts, size_t pktlen,

 			pgpDigParams mainkey, pgpDigParams **subkeys,

 			int *subkeysCount)

@@ -1264,6 +1272,13 @@ rpmRC pgpVerifySig(pgpDig dig, DIGEST_CTX hashctx)

 			      pgpDigGetParams(dig, PGPTAG_SIGNATURE), hashctx);

 }

+rpmRC pgpVerifySignature2(pgpDigParams key, pgpDigParams sig, DIGEST_CTX hashctx, char **lints)

+{

+    if (lints)

+        *lints = NULL;

+    return pgpVerifySignature(key, sig, hashctx);

+}

+

 static pgpArmor decodePkts(uint8_t *b, uint8_t **pkt, size_t *pktlen)

 {

     const char * enc = NULL;

diff --git a/rpmio/rpmpgp_sequoia.c b/rpmio/rpmpgp_sequoia.c

index e01acd0e9..2141bbf30 100644

--- a/rpmio/rpmpgp_sequoia.c

+++ b/rpmio/rpmpgp_sequoia.c

@@ -36,6 +36,9 @@ W(uint32_t, pgpDigParamsCreationTime, (pgpDigParams digp), (digp))

 W(rpmRC, pgpVerifySignature,

   (pgpDigParams key, pgpDigParams sig, DIGEST_CTX hashctx),

   (key, sig, hashctx))

+W(rpmRC, pgpVerifySignature2,

+  (pgpDigParams key, pgpDigParams sig, DIGEST_CTX hashctx, char **lints),

+  (key, sig, hashctx, lints))

 W(int, pgpPubkeyKeyID,

   (const uint8_t * pkt, size_t pktlen, pgpKeyID_t keyid),

   (pkt, pktlen, keyid))

@@ -51,6 +54,10 @@ W(int, pgpPubKeyCertLen,

 W(int, pgpPrtParams,

   (const uint8_t *pkts, size_t pktlen, unsigned int pkttype, pgpDigParams *ret),

   (pkts, pktlen, pkttype, ret))

+W(int, pgpPrtParams2,

+  (const uint8_t *pkts, size_t pktlen, unsigned int pkttype, pgpDigParams *ret,

+   char **lints),

+  (pkts, pktlen, pkttype, ret, lints))

 W(int, pgpPrtParamsSubkeys,

   (const uint8_t *pkts, size_t pktlen,

    pgpDigParams mainkey, pgpDigParams **subkeys,

diff --git a/tests/rpmi.at b/tests/rpmi.at

index 7c8f25eff..d67185d5b 100644

--- a/tests/rpmi.at

+++ b/tests/rpmi.at

@@ -254,7 +254,7 @@ AT_CLEANUP

 AT_SETUP([rpm -U <corrupted signed 1>])

 AT_KEYWORDS([install])

-AT_CHECK([

+AT_CHECK_UNQUOTED([

 RPMDB_INIT

 pkg="hello-2.0-1.x86_64-signed.rpm"

@@ -267,7 +267,13 @@ runroot rpm -U --ignorearch --ignoreos --nodeps \

 ],

 [1],

 [],

-[error: /tmp/hello-2.0-1.x86_64-signed.rpm: Header RSA signature: BAD (package tag 268: invalid OpenPGP signature)

+[`if test x$PGP = xinternal; then

+    echo 'error: /tmp/hello-2.0-1.x86_64-signed.rpm: Header RSA signature: BAD (package tag 268: invalid OpenPGP signature)'

+else

+    echo 'error: /tmp/hello-2.0-1.x86_64-signed.rpm: Header RSA signature: BAD (package tag 268: invalid OpenPGP signature: Parsing an OpenPGP packet:'

+    echo '  Failed to parse Signature Packet'

+    echo '      because: Malformed packet: Subpacket extends beyond the end of the subpacket area)'

+fi`

 error: /tmp/hello-2.0-1.x86_64-signed.rpm cannot be installed

 ])

 AT_CLEANUP

diff --git a/tests/rpmsigdig.at b/tests/rpmsigdig.at

index 5b1c6c4a6..e5482735a 100644

--- a/tests/rpmsigdig.at

+++ b/tests/rpmsigdig.at

@@ -539,7 +539,7 @@ AT_CLEANUP

 # Test pre-built corrupted package verification (corrupted signature)

 AT_SETUP([rpmkeys -Kv <corrupted signed> 1])

 AT_KEYWORDS([rpmkeys digest signature])

-AT_CHECK([

+AT_CHECK_UNQUOTED([

 RPMDB_INIT

 pkg="hello-2.0-1.x86_64-signed.rpm"

@@ -553,14 +553,28 @@ runroot rpmkeys -Kv /tmp/${pkg}

 ],

 [1],

 [/tmp/hello-2.0-1.x86_64-signed.rpm:

-    Header RSA signature: BAD (package tag 268: invalid OpenPGP signature)

+`if test x$PGP = xinternal; then

+    echo '    Header RSA signature: BAD (package tag 268: invalid OpenPGP signature)'

+else

+    echo '    Header RSA signature: BAD (package tag 268: invalid OpenPGP signature: Parsing an OpenPGP packet:'

+    echo '  Failed to parse Signature Packet'

+    echo '      because: Signature appears to be created by a non-conformant OpenPGP implementation, see <https://github.com/rpm-software-management/rpm/issues/2351>.'

+    echo '      because: Malformed MPI: leading bit is not set: expected bit 1 to be set in        0 (0))'

+fi`

     Header SHA256 digest: OK

     Header SHA1 digest: OK

     Payload SHA256 digest: OK

     V4 RSA/SHA256 Signature, key ID 1964c5fc: NOKEY

     MD5 digest: OK

 /tmp/hello-2.0-1.x86_64-signed.rpm:

-    Header RSA signature: BAD (package tag 268: invalid OpenPGP signature)

+`if test x$PGP = xinternal; then

+    echo '    Header RSA signature: BAD (package tag 268: invalid OpenPGP signature)'

+else

+    echo '    Header RSA signature: BAD (package tag 268: invalid OpenPGP signature: Parsing an OpenPGP packet:'

+    echo '  Failed to parse Signature Packet'

+    echo '      because: Signature appears to be created by a non-conformant OpenPGP implementation, see <https://github.com/rpm-software-management/rpm/issues/2351>.'

+    echo '      because: Malformed MPI: leading bit is not set: expected bit 1 to be set in        0 (0))'

+fi`

     Header SHA256 digest: OK

     Header SHA1 digest: OK

     Payload SHA256 digest: OK

-- 

2.40.0