From b4aa79da87e8463acf5877c77616199cb0ba41d7 Mon Sep 17 00:00:00 2001
From: Sridhar Markonda <sridharm@linux.ibm.com>
Date: Mon, 22 Jun 2026 00:01:50 -0500
Subject: [PATCH 1/9] pkcs7: Parse all certificates embedded in PKCS #7
 SignedData

The PKCS7 parser is extended to parse multiple certificates from
the certificate set, instead of assuming a single signer certificate.

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
---
 include/mbedtls/pkcs7.h |  11 ++-
 library/pkcs7.c         | 170 ++++++++++++++++++++++++++++------------
 2 files changed, 130 insertions(+), 51 deletions(-)

diff --git a/include/mbedtls/pkcs7.h b/include/mbedtls/pkcs7.h
index aa9764e19a..96ca302b20 100644
--- a/include/mbedtls/pkcs7.h
+++ b/include/mbedtls/pkcs7.h
@@ -121,6 +121,15 @@ typedef struct mbedtls_pkcs7_signer_info {
 }
 mbedtls_pkcs7_signer_info;
 
+/**
+ * Structure for holding a certificate in a PKCS #7 SignedData
+ */
+typedef struct mbedtls_pkcs7_cert {
+    mbedtls_x509_crt MBEDTLS_PRIVATE(cert);
+    struct mbedtls_pkcs7_cert *MBEDTLS_PRIVATE(next);
+}
+mbedtls_pkcs7_cert;
+
 /**
  * Structure holding the signed data section
  */
@@ -128,7 +137,7 @@ typedef struct mbedtls_pkcs7_signed_data {
     int MBEDTLS_PRIVATE(version);
     mbedtls_pkcs7_buf MBEDTLS_PRIVATE(digest_alg_identifiers);
     int MBEDTLS_PRIVATE(no_of_certs);
-    mbedtls_x509_crt MBEDTLS_PRIVATE(certs);
+    mbedtls_pkcs7_cert *MBEDTLS_PRIVATE(certs);
     int MBEDTLS_PRIVATE(no_of_crls);
     mbedtls_x509_crl MBEDTLS_PRIVATE(crl);
     int MBEDTLS_PRIVATE(no_of_signers);
diff --git a/library/pkcs7.c b/library/pkcs7.c
index 4e3b554f0e..bbd71842ca 100644
--- a/library/pkcs7.c
+++ b/library/pkcs7.c
@@ -20,6 +20,7 @@
 
 #include "mbedtls/platform.h"
 #include "mbedtls/platform_util.h"
+#include <limits.h>
 
 #if defined(MBEDTLS_HAVE_TIME)
 #include "mbedtls/platform_time.h"
@@ -158,62 +159,121 @@ static int pkcs7_get_digest_algorithm_set(unsigned char **p,
 }
 
 /**
- * certificates :: SET OF ExtendedCertificateOrCertificate,
- * ExtendedCertificateOrCertificate ::= CHOICE {
- *      certificate Certificate -- x509,
- *      extendedCertificate[0] IMPLICIT ExtendedCertificate }
- * Return number of certificates added to the signed data,
- * 0 or higher is valid.
- * Return negative error code for failure.
- **/
-static int pkcs7_get_certificates(unsigned char **p, unsigned char *end,
-                                  mbedtls_x509_crt *certs)
+ * \brief           Parse and add a certificate to the certificate list.
+ *
+ * \details         Decodes a DER-encoded certificate and adds it to the
+ *                  certificate list.
+ *
+ * \param der_cert  DER-encoded certificate.
+ * \param der_len   Length of the DER-encoded certificate.
+ * \param certs     Certificate list to which the parsed certificate
+ *                  is added.
+ *
+ * \return          0 on success, or a negative error code on failure.
+ */
+static int pkcs7_parse_cert_der(const unsigned char *der_cert, size_t der_len,
+                                mbedtls_pkcs7_cert **certs)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t len1 = 0;
-    size_t len2 = 0;
-    unsigned char *end_set, *end_cert, *start;
+    mbedtls_pkcs7_cert *pcert;
 
-    ret = mbedtls_asn1_get_tag(p, end, &len1, MBEDTLS_ASN1_CONSTRUCTED
-                               | MBEDTLS_ASN1_CONTEXT_SPECIFIC);
-    if (ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
-        return 0;
+    pcert = mbedtls_calloc(1, sizeof(mbedtls_pkcs7_cert));
+    if (pcert == NULL) {
+        return MBEDTLS_ERR_PKCS7_ALLOC_FAILED;
     }
+
+    mbedtls_x509_crt_init(&pcert->cert);
+
+    ret = mbedtls_x509_crt_parse_der(&pcert->cert, der_cert, der_len);
     if (ret != 0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_FORMAT, ret);
-    }
-    start = *p;
-    end_set = *p + len1;
-
-    ret = mbedtls_asn1_get_tag(p, end_set, &len2, MBEDTLS_ASN1_CONSTRUCTED
-                               | MBEDTLS_ASN1_SEQUENCE);
-    if (ret != 0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_CERT, ret);
-    }
-
-    end_cert = *p + len2;
-
-    /*
-     * This is to verify that there is only one signer certificate. It seems it is
-     * not easy to differentiate between the chain vs different signer's certificate.
-     * So, we support only the root certificate and the single signer.
-     * The behaviour would be improved with addition of multiple signer support.
-     */
-    if (end_cert != end_set) {
-        return MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE;
-    }
-
-    if ((ret = mbedtls_x509_crt_parse_der(certs, start, len1)) < 0) {
+        mbedtls_free(pcert);
         return MBEDTLS_ERR_PKCS7_INVALID_CERT;
     }
 
-    *p = end_cert;
+    if (*certs == NULL) {
+        *certs = pcert;
+    } else {
+        pcert->next = *certs;
+        *certs = pcert;
+    }
 
-    /*
-     * Since in this version we strictly support single certificate, and reaching
-     * here implies we have parsed successfully, we return 1.
-     */
-    return 1;
+    return 0;
+}
+
+/**
+ * \brief           Parse certificates from PKCS#7 SignedData.
+ *
+ * \details         Parses the SET OF ExtendedCertificateOrCertificate and
+ *                  stores them in a linked list of mbedtls_pkcs7_cert nodes.
+ *
+ *                  certificates :: SET OF ExtendedCertificateOrCertificate,
+ *                  ExtendedCertificateOrCertificate ::= CHOICE {
+ *                       certificate Certificate -- x509,
+ *                       extendedCertificate[0] IMPLICIT ExtendedCertificate
+ *                  }
+ *
+ * \param p         Input pointer to ASN.1 buffer.
+ * \param end       End of input buffer.
+ * \param certs     Certificate list.
+ *
+ * \return          Number of certificates parsed (>= 0) on success,
+ *                  or a negative error code on failure.
+ */
+static int pkcs7_get_certificates(unsigned char **p, unsigned char *end,
+                                  mbedtls_pkcs7_cert **certs)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t set_len = 0;
+    int count = 0;
+    unsigned char *end_set;
+
+    ret = mbedtls_asn1_get_tag(p, end, &set_len,
+                               MBEDTLS_ASN1_CONSTRUCTED |
+                               MBEDTLS_ASN1_CONTEXT_SPECIFIC);
+    if (ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
+        return 0;
+    } else if (ret != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_FORMAT, ret);
+    }
+
+    end_set = *p + set_len;
+
+    while (*p < end_set && count < INT_MAX) {
+        unsigned char *elem_start = *p;
+        unsigned char *q = *p;
+        size_t cert_len = 0;
+        size_t der_len;
+
+        ret = mbedtls_asn1_get_tag(&q, end_set, &cert_len,
+                                   MBEDTLS_ASN1_CONSTRUCTED |
+                                   MBEDTLS_ASN1_SEQUENCE);
+        if (ret != 0) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_CERT,
+                                     ret);
+        }
+
+        if (cert_len > (size_t) (end_set - q)) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_FORMAT,
+                                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+        }
+
+        der_len = (size_t) ((q + cert_len) - elem_start);
+
+        ret = pkcs7_parse_cert_der(elem_start, der_len, certs);
+        if (ret != 0) {
+            return ret;
+        }
+
+        *p = q + cert_len;
+        count++;
+    }
+
+    if (*p != end_set) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    return count;
 }
 
 /**
@@ -514,14 +574,13 @@ static int pkcs7_get_signed_data(unsigned char *buf, size_t buflen,
     }
 
     /* Look for certificates, there may or may not be any */
-    mbedtls_x509_crt_init(&signed_data->certs);
+    signed_data->certs = NULL;
     ret = pkcs7_get_certificates(&p, end, &signed_data->certs);
     if (ret < 0) {
         return ret;
     }
 
     signed_data->no_of_certs = ret;
-
     /*
      * Currently CRLs are not supported. If CRL exist, the parsing will fail
      * at next step of getting signers info and return error as invalid
@@ -759,6 +818,8 @@ void mbedtls_pkcs7_free(mbedtls_pkcs7 *pkcs7)
 {
     mbedtls_pkcs7_signer_info *signer_cur;
     mbedtls_pkcs7_signer_info *signer_prev;
+    mbedtls_pkcs7_cert *cert_cur;
+    mbedtls_pkcs7_cert *cert_prev;
 
     if (pkcs7 == NULL || pkcs7->raw.p == NULL) {
         return;
@@ -766,7 +827,16 @@ void mbedtls_pkcs7_free(mbedtls_pkcs7 *pkcs7)
 
     mbedtls_free(pkcs7->raw.p);
 
-    mbedtls_x509_crt_free(&pkcs7->signed_data.certs);
+    cert_cur = pkcs7->signed_data.certs;
+    while (cert_cur != NULL) {
+        cert_prev = cert_cur;
+        cert_cur = cert_cur->next;
+        mbedtls_x509_crt_free(&cert_prev->cert);
+        mbedtls_free(cert_prev);
+    }
+
+    pkcs7->signed_data.certs = NULL;
+
     mbedtls_x509_crl_free(&pkcs7->signed_data.crl);
 
     signer_cur = pkcs7->signed_data.signers.next;

From 31cd11e04b4f46cc184c47737554c0daf5250082 Mon Sep 17 00:00:00 2001
From: Sridhar Markonda <sridharm@linux.ibm.com>
Date: Fri, 28 Aug 2026 01:14:20 -0500
Subject: [PATCH 2/9] tests: Allow PKCS #7 parsing with multiple certificates

The PKCS#7 parser supports multiple embedded certificates.
Update the test expectation to treat SignedData with multiple certificates
as valid instead of returning MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE.

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
---
 tests/suites/test_suite_pkcs7.data | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/suites/test_suite_pkcs7.data b/tests/suites/test_suite_pkcs7.data
index 4aff54c1cc..7d0a0710f4 100644
--- a/tests/suites/test_suite_pkcs7.data
+++ b/tests/suites/test_suite_pkcs7.data
@@ -22,9 +22,9 @@ PKCS7 Signed Data Parse reused object from multiple signers to one signer
 depends_on:PSA_WANT_ALG_SHA_256:PSA_WANT_KEY_TYPE_RSA_PUBLIC_KEY
 pkcs7_parse_reuse:"../framework/data_files/pkcs7_data_multiple_signed.der":"../framework/data_files/pkcs7_data_cert_signed_sha256.der":MBEDTLS_PKCS7_SIGNED_DATA
 
-PKCS7 Signed Data Parse Fail with multiple certs #4
+PKCS7 Signed Data Parse Pass with multiple certs #4
 depends_on:PSA_WANT_ALG_SHA_256:PSA_WANT_KEY_TYPE_RSA_PUBLIC_KEY
-pkcs7_parse:"../framework/data_files/pkcs7_data_multiple_certs_signed.der":MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE
+pkcs7_parse:"../framework/data_files/pkcs7_data_multiple_certs_signed.der":MBEDTLS_PKCS7_SIGNED_DATA
 
 PKCS7 Signed Data Parse Fail with corrupted cert #5.0
 depends_on:PSA_WANT_ALG_SHA_256:PSA_WANT_KEY_TYPE_RSA_PUBLIC_KEY

From 89cc0b2cb4bb4f4f23388eca5e5bdd9c1f2fe0a4 Mon Sep 17 00:00:00 2001
From: Sridhar Markonda <sridharm@linux.ibm.com>
Date: Tue, 1 Sep 2026 13:30:17 -0500
Subject: [PATCH 3/9] pkcs7: Add certificate chain verification and extended
 APIs

Extend PKCS#7 SignedData verification to support building and
verifying the certificate chain of the signer.

Add extended signature verification APIs that use caller-supplied
trusted certificates and optionally embedded leaf certificates
from the PKCS#7 structure. When embedded leaf certificates are used,
their certificate chain is validated against the provided trusted CAs.

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
---
 include/mbedtls/pkcs7.h |  76 ++++++-
 library/pkcs7.c         | 425 +++++++++++++++++++++++++++++++++++++---
 2 files changed, 469 insertions(+), 32 deletions(-)

diff --git a/include/mbedtls/pkcs7.h b/include/mbedtls/pkcs7.h
index 96ca302b20..9d89158bc2 100644
--- a/include/mbedtls/pkcs7.h
+++ b/include/mbedtls/pkcs7.h
@@ -63,6 +63,8 @@
 #define MBEDTLS_ERR_PKCS7_ALLOC_FAILED                     PSA_ERROR_INSUFFICIENT_MEMORY  /**< Allocation of memory failed. */
 #define MBEDTLS_ERR_PKCS7_VERIFY_FAIL                      PSA_ERROR_INVALID_SIGNATURE  /**< Verification Failed */
 #define MBEDTLS_ERR_PKCS7_CERT_DATE_INVALID                -0x5880  /**< The PKCS #7 date issued/expired dates are invalid */
+#define MBEDTLS_ERR_PKCS7_CERT_VERIFY_FAILED               -0x5900  /**< The PKCS #7 signer certificate verification failed. */
+#define MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND            -0x5980  /**< No certificate matching the PKCS#7 signer information was found. */
 /* \} name */
 
 /**
@@ -208,7 +210,7 @@ int mbedtls_pkcs7_parse_der(mbedtls_pkcs7 *pkcs7, const unsigned char *buf,
  *
  * \return         0 if the signature verifies, or a negative error code on failure.
  */
-int mbedtls_pkcs7_signed_data_verify(mbedtls_pkcs7 *pkcs7,
+int mbedtls_pkcs7_signed_data_verify(const mbedtls_pkcs7 *pkcs7,
                                      const mbedtls_x509_crt *cert,
                                      const unsigned char *data,
                                      size_t datalen);
@@ -240,10 +242,80 @@ int mbedtls_pkcs7_signed_data_verify(mbedtls_pkcs7 *pkcs7,
  *
  * \return         0 if the signature verifies, or a negative error code on failure.
  */
-int mbedtls_pkcs7_signed_hash_verify(mbedtls_pkcs7 *pkcs7,
+int mbedtls_pkcs7_signed_hash_verify(const mbedtls_pkcs7 *pkcs7,
                                      const mbedtls_x509_crt *cert,
                                      const unsigned char *hash, size_t hashlen);
 
+/**
+ * \brief                 Verify a PKCS #7 SignedData signature over plain data.
+ *
+ *                        For each signer in the PKCS#7 structure, this function verifies
+ *                        the signature over the supplied data using the digest algorithm
+ *                        specified by the signer and a matching leaf certificate.
+ *                        Verification succeeds if at least one signer signature is valid.
+ *
+ *                        The verification uses certificates provided by the caller and,
+ *                        optionally, certificates embedded within the PKCS#7 SignedData
+ *                        structure. When certificates from the PKCS#7 structure are used,
+ *                        the signer certificate chain is validated against the supplied
+ *                        trusted certificates.
+ *
+ * \param pkcs7           PKCS#7 SignedData structure containing signatures.
+ * \param trust_certs     Certificate list containing trusted leaf and CA certificates.
+ *                        CA certificates are used for certificate chain verification and
+ *                        leaf certificates are used for signature verification.
+ * \param data            Plain data on which signature has to be verified.
+ * \param datalen         Length of the \p data.
+ * \param use_pkcs7_leaf  Flag indicating whether to use the leaf certificate embedded
+ *                        in the PKCS#7 structure: set to \c 1 to enforce use of the PKCS#7
+ *                        leaf certificate, or \c 0 to use only caller-supplied certificates.
+ *
+ * \note                  This function internally calculates the hash on the supplied
+ *                        plain data for signature verification.
+ *
+ * \return                0 on success, or a negative error code on failure.
+ */
+int mbedtls_pkcs7_signed_data_verify_ext(const mbedtls_pkcs7 *pkcs7,
+                                         const mbedtls_x509_crt *trust_certs,
+                                         const unsigned char *data,
+                                         const size_t datalen,
+                                         const int use_pkcs7_leaf);
+
+/**
+ * \brief                 Verify PKCS #7 SignedData signature over a supplied hash.
+ *
+ *                        For each signer in the PKCS#7 structure, this function verifies
+ *                        the signature over the supplied message hash using the digest
+ *                        algorithm specified by the signer and a matching leaf certificate.
+ *                        Verification succeeds if at least one signer signature is valid.
+ *
+ *                        The verification uses certificates provided by the caller and,
+ *                        optionally, certificates embedded within the PKCS#7 SignedData
+ *                        structure. When certificates from the PKCS#7 structure are used,
+ *                        the signer certificate chain is validated against the supplied
+ *                        trusted certificates.
+ *
+ * \param pkcs7           PKCS #7 SignedData structure containing signatures.
+ * \param trust_certs     Certificate list containing trusted leaf and CA certificates.
+ *                        CA certificates are used for certificate chain verification and
+ *                        leaf certificates are used for signature verification.
+ * \param hash            Hash of the plain data on which signature has to be verified.
+ * \param hashlen         Length of the \p hash.
+ * \param use_pkcs7_leaf  Flag indicating whether to use the leaf certificate embedded in
+ *                        the PKCS#7 structure: set to \c 1 to enforce use of the PKCS#7
+ *                        leaf certificate, or \c 0 to use only caller-supplied certificates.
+ *
+ * \note                  This function differs from mbedtls_pkcs7_signed_data_verify_ext()
+ *                        in that the hash of the input data is provided directly by caller.
+ *
+ * \return                0 on success, or a negative error code on failure.
+ */
+int mbedtls_pkcs7_signed_hash_verify_ext(const mbedtls_pkcs7 *pkcs7,
+                                         const mbedtls_x509_crt *trust_certs,
+                                         const unsigned char *hash,
+                                         const size_t hashlen,
+                                         const int use_pkcs7_leaf);
+
 /**
  * \brief          Unallocate all PKCS #7 data and zeroize the memory.
  *                 It doesn't free \p pkcs7 itself. This should be done by the caller.
diff --git a/library/pkcs7.c b/library/pkcs7.c
index bbd71842ca..7f58569e4d 100644
--- a/library/pkcs7.c
+++ b/library/pkcs7.c
@@ -697,20 +697,258 @@ out:
     return ret;
 }
 
-static int mbedtls_pkcs7_data_or_hash_verify(mbedtls_pkcs7 *pkcs7,
-                                             const mbedtls_x509_crt *cert,
-                                             const unsigned char *data,
-                                             size_t datalen,
-                                             const int is_data_hash)
+/**
+ * \brief      Decide whether a certificate should be classified as a CA.
+ *             Policy:
+ *              - If BasicConstraints present and CA=TRUE => CA
+ *              - If KeyUsage is present, require keyCertSign for CA
+ *              - If BasicConstraints absent => NOT a CA (classify as leaf)
+ *              - If BasicConstraints is present and CA=FALSE => not a CA (leaf)
+ *
+ * \param crt  Certificate to classify.
+ *
+ * \return     1 if the certificate is classified as CA, 0 otherwise.
+ */
+static int pkcs7_is_ca_cert(const mbedtls_x509_crt *crt)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    unsigned char *hash;
-    mbedtls_pk_context pk_cxt = cert->pk;
-    const mbedtls_md_info_t *md_info;
-    mbedtls_md_type_t md_alg;
-    mbedtls_pkcs7_signer_info *signer;
+    /* BasicConstraints: is CA? */
+    ret = mbedtls_x509_crt_get_ca_istrue(crt);
+    if (ret == 1) {
+        /* CA=TRUE; enforce keyCertSign only if KU exists  */
+        ret = mbedtls_x509_crt_check_key_usage(crt, MBEDTLS_X509_KU_KEY_CERT_SIGN);
+        return (ret == 0) ? 1 : 0;
+    } else {
+        /* ret == 0: BC present, CA=FALSE.  ret < 0: BasicConstraints absent) */
+        return 0;
+    }
+}
 
-    if (pkcs7->signed_data.no_of_signers == 0) {
+/**
+ * \brief           Check if the given CA certificate is a possible issuer of
+ *                  the provided certificate.
+ * \details         This function attempts to match the issuer of \p cert with
+ *                  the subject of \p ca using the following order:
+ *                  1. If both AKI keyIdentifier and SKI are present, compare them.
+ *                  2. If AKI authorityCertIssuer and authorityCertSerialNumber are
+ *                     present, compare against the CA's subject DN and serial.
+ *                  3. Fallback to comparing issuer and subject Distinguished Name (DN).
+ *
+ * \param cert      The certificate whose issuer is to be found.
+ * \param ca        Candidate CA certificate.
+ *
+ * \return          0 if \p ca is a potential issuer of \p cert, -1 otherwise.
+ */
+static int pkcs7_is_issuer_match(const mbedtls_x509_crt *cert,
+                                 const mbedtls_x509_crt *ca)
+{
+    if (cert->authority_key_id.keyIdentifier.len != 0 &&
+        ca->subject_key_id.len != 0) {
+
+        if (cert->authority_key_id.keyIdentifier.len == ca->subject_key_id.len &&
+            memcmp(cert->authority_key_id.keyIdentifier.p, ca->subject_key_id.p,
+                   ca->subject_key_id.len) == 0) {
+            return 0;
+        }
+
+        return -1;
+    }
+
+    if (cert->authority_key_id.authorityCertIssuer.buf.len != 0 &&
+        cert->authority_key_id.authorityCertSerialNumber.len != 0) {
+
+        if (cert->authority_key_id.authorityCertIssuer.buf.len == ca->subject_raw.len &&
+            memcmp(cert->authority_key_id.authorityCertIssuer.buf.p,
+                   ca->subject_raw.p, ca->subject_raw.len) == 0 &&
+            cert->authority_key_id.authorityCertSerialNumber.len == ca->serial.len &&
+            memcmp(cert->authority_key_id.authorityCertSerialNumber.p,
+                   ca->serial.p, ca->serial.len) == 0) {
+            return 0;
+        }
+
+        return -1;
+    }
+
+    if (cert->issuer_raw.len == ca->subject_raw.len &&
+        memcmp(cert->issuer_raw.p, ca->subject_raw.p,
+               cert->issuer_raw.len) == 0) {
+        return 0;
+    }
+
+    return -1;
+}
+
+/**
+ * \brief            Check if a certificate already exist in the chain
+ *                   by comparing TBSCertificate content.
+ *
+ * \param chain      The certificate chain to search
+ * \param cert       The certificate to look for
+ *
+ * \return           1 if certificate exists in chain
+ *                   0 if certificate does not exist
+ */
+static int pkcs7_is_duplicate_cert(const mbedtls_x509_crt *chain,
+                                   const mbedtls_x509_crt *cert)
+{
+    const mbedtls_x509_crt *cur;
+
+    for (cur = chain; cur != NULL; cur = cur->next) {
+        if (cur->tbs.len != cert->tbs.len) {
+            continue;
+        }
+
+        if (memcmp(cur->tbs.p, cert->tbs.p, cert->tbs.len) == 0) {
+            return 1;
+        }
+    }
+
+    return 0;
+}
+
+/**
+ * \brief              Build CA certificate chain from embedded PKCS#7 certs.
+ *
+ * \param pkcs7_certs  Embedded certificate list (mbedtls_pkcs7_cert).
+ * \param leaf_cert    Leaf certificate to build chain for.
+ * \param ca_chain     On success, pointer to CA chain (caller must free).
+ *
+ * \return             0 on success, or a negative error code on failure.
+ */
+static int pkcs7_build_ca_chain(const mbedtls_pkcs7_cert *pkcs7_certs,
+                                const mbedtls_x509_crt *leaf_cert,
+                                mbedtls_x509_crt **ca_chain)
+{
+    const mbedtls_x509_crt *current = leaf_cert;
+    const mbedtls_pkcs7_cert *embedded_cert;
+    mbedtls_x509_crt *chain = NULL;
+    int ret;
+    size_t depth = 0;
+
+    *ca_chain = NULL;
+
+    while (depth < MBEDTLS_X509_MAX_INTERMEDIATE_CA && current != NULL) {
+        int found = 0;
+
+        for (embedded_cert = pkcs7_certs; embedded_cert != NULL;
+             embedded_cert = embedded_cert->next) {
+            const mbedtls_x509_crt *issuer = &embedded_cert->cert;
+
+            if (issuer->raw.p == NULL || issuer->raw.len == 0) {
+                continue;
+            }
+
+            if (issuer == current) {
+                continue;
+            }
+
+            if (pkcs7_is_ca_cert(issuer) != 1) {
+                continue;
+            }
+
+            if (pkcs7_is_issuer_match(current, issuer) == 0) {
+                if (pkcs7_is_duplicate_cert(chain, issuer)) {
+                    continue;
+                }
+
+                if (chain == NULL) {
+                    chain = mbedtls_calloc(1, sizeof(mbedtls_x509_crt));
+                    if (chain == NULL) {
+                        ret =  MBEDTLS_ERR_PKCS7_ALLOC_FAILED;
+                        goto cleanup;
+                    }
+                    mbedtls_x509_crt_init(chain);
+                }
+
+                ret = mbedtls_x509_crt_parse_der(chain, issuer->raw.p, issuer->raw.len);
+                if (ret != 0) {
+                    goto cleanup;
+                }
+
+                current = issuer;
+                found = 1;
+                depth++;
+                break;
+            }
+        }
+
+        if (!found) {
+            break;
+        }
+    }
+
+    *ca_chain = chain;
+    return 0;
+
+cleanup:
+    if (chain != NULL) {
+        mbedtls_x509_crt_free(chain);
+        mbedtls_free(chain);
+    }
+    return ret;
+}
+
+/**
+ * \brief              Verify certificate chain against trusted anchors.
+ *
+ * \details            Builds CA chain from embedded PKCS#7 certs and verifies
+ *                     the complete chain against trust anchors.
+ *
+ * \note               mbedtls_x509_crt_verify() accepts mixed list of trusted
+ *                     CAs and trusted leaf certs.
+ *
+ * \param pkcs7_certs    Embedded certificate list
+ * \param leaf_cert      Leaf certificate to verify.
+ * \param trust_anchors  Trust anchors: root CAs and/or trusted leaf certs.
+ *
+ * \return               0 on success, or a negative error code on failure.
+ */
+static int pkcs7_verify_chain(const mbedtls_pkcs7_cert *pkcs7_certs,
+                              mbedtls_x509_crt *leaf_cert,
+                              const mbedtls_x509_crt *trust_anchors)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    mbedtls_x509_crt *ca_chain = NULL;
+    uint32_t flags = 0;
+
+    ret = pkcs7_build_ca_chain(pkcs7_certs, leaf_cert, &ca_chain);
+    if (ret != 0) {
+        return ret;
+    }
+
+    leaf_cert->next = ca_chain;
+    ret = mbedtls_x509_crt_verify(leaf_cert, (mbedtls_x509_crt *) trust_anchors,
+                                  NULL, NULL, &flags, NULL, NULL);
+
+    leaf_cert->next = NULL;
+
+    if (ca_chain != NULL) {
+        mbedtls_x509_crt_free(ca_chain);
+        mbedtls_free(ca_chain);
+    }
+
+    if (ret != 0 || flags != 0) {
+        return MBEDTLS_ERR_PKCS7_CERT_VERIFY_FAILED;
+    }
+
+    return 0;
+}
+
+/**
+ * \brief           Check if certificate matches signer info.
+ *
+ * \details         Validates certificate date, matches serial/issuer,
+ *                  and checks key usage for digital signature.
+ *
+ * \param cert      Certificate to check.
+ * \param signer    Signer info to match against.
+ *
+ * \return          0 if match, or a negative error code otherwise.
+ */
+static int pkcs7_check_cert_with_signer(const mbedtls_x509_crt *cert,
+                                        const mbedtls_pkcs7_signer_info *signer)
+{
+    if (cert->raw.p == NULL || cert->raw.len == 0) {
         return MBEDTLS_ERR_PKCS7_INVALID_CERT;
     }
 
@@ -719,6 +957,96 @@ static int mbedtls_pkcs7_data_or_hash_verify(mbedtls_pkcs7 *pkcs7,
         return MBEDTLS_ERR_PKCS7_CERT_DATE_INVALID;
     }
 
+    if (cert->serial.len != signer->serial.len ||
+        memcmp(cert->serial.p, signer->serial.p, signer->serial.len) != 0) {
+        return MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND;
+    }
+
+    if (cert->issuer_raw.len != signer->issuer_raw.len ||
+        memcmp(cert->issuer_raw.p, signer->issuer_raw.p,
+               signer->issuer_raw.len) != 0) {
+        return MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND;
+    }
+
+    if (mbedtls_x509_crt_check_key_usage(cert,
+                                         MBEDTLS_X509_KU_DIGITAL_SIGNATURE) != 0) {
+        return MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND;
+    }
+
+    return 0;
+}
+
+/**
+ * \brief                Find matching leaf certificate.
+ *
+ * \details              Searches for certificate matching signer info.
+ *                       Can search in embedded PKCS#7 certs or external chain.
+ *
+ * \param pkcs7          PKCS#7 structure (for embedded certs).
+ * \param certs          External certificate chain.
+ * \param signer         Signer info to match against.
+ * \param use_pkcs7_leaf Flag: 1=search embedded, 0=search external.
+ * \param leaf_cert      On success, pointer to matching certificate.
+ *
+ * \return               0 on success, or a negative error code on failure.
+ */
+static int pkcs7_get_leaf_cert(const mbedtls_pkcs7 *pkcs7,
+                               const mbedtls_x509_crt *certs,
+                               const mbedtls_pkcs7_signer_info *signer,
+                               const int use_pkcs7_leaf,
+                               mbedtls_x509_crt **leaf_cert)
+{
+    int ret = MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND;
+
+    if (use_pkcs7_leaf == 1) {
+        const mbedtls_pkcs7_cert *embedded_cert = pkcs7->signed_data.certs;
+
+        while (embedded_cert != NULL) {
+            const mbedtls_x509_crt *cert = &embedded_cert->cert;
+
+            ret = pkcs7_check_cert_with_signer(cert, signer);
+            if (ret == 0) {
+                *leaf_cert = (mbedtls_x509_crt *) cert;
+                return 0;
+            }
+
+            embedded_cert = embedded_cert->next;
+        }
+    } else {
+        const mbedtls_x509_crt *cert = certs;
+
+        while (cert != NULL) {
+            ret = pkcs7_check_cert_with_signer(cert, signer);
+            if (ret == 0) {
+                *leaf_cert = (mbedtls_x509_crt *) cert;
+                return 0;
+            }
+
+            cert = cert->next;
+        }
+    }
+
+    return ret;
+}
+
+static int mbedtls_pkcs7_data_or_hash_verify(const mbedtls_pkcs7 *pkcs7,
+                                             const mbedtls_x509_crt *cert,
+                                             const unsigned char *data,
+                                             size_t datalen,
+                                             const int is_data_hash,
+                                             const int use_pkcs7_leaf)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    unsigned char *hash = NULL;
+    const mbedtls_md_info_t *md_info;
+    mbedtls_md_type_t md_alg;
+    const mbedtls_pkcs7_signer_info *signer;
+    mbedtls_x509_crt *leaf_cert = NULL;
+
+    if (pkcs7->signed_data.no_of_signers == 0) {
+        return MBEDTLS_ERR_PKCS7_INVALID_CERT;
+    }
+
     ret = mbedtls_x509_oid_get_md_alg(&pkcs7->signed_data.digest_alg_identifiers, &md_alg);
     if (ret != 0) {
         return ret;
@@ -764,21 +1092,26 @@ static int mbedtls_pkcs7_data_or_hash_verify(mbedtls_pkcs7 *pkcs7,
     /* assume failure */
     ret = MBEDTLS_ERR_PKCS7_VERIFY_FAIL;
 
-    /*
-     * Potential TODOs
-     * Currently we iterate over all signers and return success if any of them
-     * verify.
-     *
-     * However, we could make this better by checking against the certificate's
-     * identification and SignerIdentifier fields first. That would also allow
-     * us to distinguish between 'no signature for key' and 'signature for key
-     * failed to validate'.
-     */
     for (signer = &pkcs7->signed_data.signers; signer; signer = signer->next) {
-        ret = mbedtls_pk_verify_ext(cert->sig_pk, &pk_cxt, md_alg, hash,
-                                    mbedtls_md_get_size(md_info),
-                                    signer->sig.p, signer->sig.len);
+        if (signer->sig.p == NULL || signer->sig.len == 0) {
+            continue;
+        }
 
+        ret = pkcs7_get_leaf_cert(pkcs7, cert, signer, use_pkcs7_leaf, &leaf_cert);
+        if (ret != 0) {
+            continue;
+        }
+
+        if (use_pkcs7_leaf == 1) {
+            ret = pkcs7_verify_chain(pkcs7->signed_data.certs, leaf_cert, cert);
+            if (ret != 0) {
+                continue;
+            }
+        }
+
+        ret = mbedtls_pk_verify_ext(leaf_cert->sig_pk, &leaf_cert->pk, md_alg,
+                                    hash, mbedtls_md_get_size(md_info),
+                                    signer->sig.p, signer->sig.len);
         if (ret == 0) {
             break;
         }
@@ -789,26 +1122,58 @@ static int mbedtls_pkcs7_data_or_hash_verify(mbedtls_pkcs7 *pkcs7,
     return ret;
 }
 
-int mbedtls_pkcs7_signed_data_verify(mbedtls_pkcs7 *pkcs7,
+int mbedtls_pkcs7_signed_data_verify(const mbedtls_pkcs7 *pkcs7,
                                      const mbedtls_x509_crt *cert,
                                      const unsigned char *data,
                                      size_t datalen)
 {
-    if (data == NULL) {
+    if (data == NULL || pkcs7 == NULL || cert == NULL) {
         return MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA;
     }
-    return mbedtls_pkcs7_data_or_hash_verify(pkcs7, cert, data, datalen, 0);
+
+    return mbedtls_pkcs7_data_or_hash_verify(pkcs7, cert, data, datalen, 0, 0);
 }
 
-int mbedtls_pkcs7_signed_hash_verify(mbedtls_pkcs7 *pkcs7,
+int mbedtls_pkcs7_signed_hash_verify(const mbedtls_pkcs7 *pkcs7,
                                      const mbedtls_x509_crt *cert,
                                      const unsigned char *hash,
                                      size_t hashlen)
 {
-    if (hash == NULL) {
+    if (hash == NULL || pkcs7 == NULL || cert == NULL) {
         return MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA;
     }
-    return mbedtls_pkcs7_data_or_hash_verify(pkcs7, cert, hash, hashlen, 1);
+
+    return mbedtls_pkcs7_data_or_hash_verify(pkcs7, cert, hash, hashlen, 1, 0);
+}
+
+int mbedtls_pkcs7_signed_data_verify_ext(const mbedtls_pkcs7 *pkcs7,
+                                         const mbedtls_x509_crt *trust_certs,
+                                         const unsigned char *data,
+                                         const size_t datalen,
+                                         const int use_pkcs7_leaf)
+{
+    if (data == NULL || pkcs7 == NULL || trust_certs == NULL ||
+        (use_pkcs7_leaf != 0 && use_pkcs7_leaf != 1)) {
+        return MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA;
+    }
+
+    return mbedtls_pkcs7_data_or_hash_verify(pkcs7, trust_certs, data, datalen,
+                                             0, use_pkcs7_leaf);
+}
+
+int mbedtls_pkcs7_signed_hash_verify_ext(const mbedtls_pkcs7 *pkcs7,
+                                         const mbedtls_x509_crt *trust_certs,
+                                         const unsigned char *hash,
+                                         const size_t hashlen,
+                                         const int use_pkcs7_leaf)
+{
+    if (hash == NULL || pkcs7 == NULL || trust_certs == NULL ||
+        (use_pkcs7_leaf != 0 && use_pkcs7_leaf != 1)) {
+        return MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA;
+    }
+
+    return mbedtls_pkcs7_data_or_hash_verify(pkcs7, trust_certs, hash, hashlen,
+                                             1, use_pkcs7_leaf);
 }
 
 /*

From 33e538b546eec676d2ad231369b7f143ca730556 Mon Sep 17 00:00:00 2001
From: Sridhar Markonda <sridharm@linux.ibm.com>
Date: Mon, 17 Aug 2026 01:36:32 -0500
Subject: [PATCH 4/9] tests: Update PKCS#7 verification tests and add tests for
 extended APIs

Update expected return values of existing PKCS#7 verification
tests to match the new signer certificate error reporting.

Add test cases and test functions for the extended PKCS#7 signature
verification APIs, including embedded signer certificates, certificate
chain validation, and multiple signer scenarios.

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
---
 tests/suites/test_suite_pkcs7.data     | 96 +++++++++++++++++++++++++-
 tests/suites/test_suite_pkcs7.function | 91 ++++++++++++++++++++++++
 2 files changed, 185 insertions(+), 2 deletions(-)

diff --git a/tests/suites/test_suite_pkcs7.data b/tests/suites/test_suite_pkcs7.data
index 7d0a0710f4..74d1947e37 100644
--- a/tests/suites/test_suite_pkcs7.data
+++ b/tests/suites/test_suite_pkcs7.data
@@ -84,7 +84,7 @@ pkcs7_verify:"../framework/data_files/pkcs7_zerolendata_detached.der":"../framew
 
 PKCS7 Signed Data Verification Fail zero-len data
 depends_on:PSA_WANT_ALG_SHA_1:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
-pkcs7_verify:"../framework/data_files/pkcs7_zerolendata_detached.der":"../framework/data_files/pkcs7-rsa-sha256-2.der":"../framework/data_files/pkcs7_zerolendata.bin":0:MBEDTLS_ERR_RSA_VERIFY_FAILED
+pkcs7_verify:"../framework/data_files/pkcs7_zerolendata_detached.der":"../framework/data_files/pkcs7-rsa-sha256-2.der":"../framework/data_files/pkcs7_zerolendata.bin":0:MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND
 
 PKCS7 Signed Data Verification Pass SHA256 #9
 depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
@@ -112,7 +112,7 @@ pkcs7_verify:"../framework/data_files/pkcs7_data_cert_signed_sha512.der":"../fra
 
 PKCS7 Signed Data Verification Fail because of different certificate #12
 depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
-pkcs7_verify:"../framework/data_files/pkcs7_data_cert_signed_sha256.der":"../framework/data_files/pkcs7-rsa-sha256-2.der":"../framework/data_files/pkcs7_data.bin":0:MBEDTLS_ERR_RSA_VERIFY_FAILED
+pkcs7_verify:"../framework/data_files/pkcs7_data_cert_signed_sha256.der":"../framework/data_files/pkcs7-rsa-sha256-2.der":"../framework/data_files/pkcs7_data.bin":0:MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND
 
 PKCS7 Signed Data Verification Fail because of different data hash #13
 depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
@@ -3271,3 +3271,95 @@ pkcs7_asn1_fail:"3082049d06092a864886f70d010702a082048e3082048a020101310f300d060
 PKCS7 Parse Failure Invalid ASN1: Change length from 256 to 257 #794.0
 depends_on:PSA_WANT_ALG_SHA_256
 pkcs7_asn1_fail:"3082049d06092a864886f70d010702a082048e3082048a020101310f300d06096086480165030402010500300b06092a864886f70d0107013182046530820173020101304c3034310b3009060355040613024e4c310e300c060355040a0c05504b4353373115301306035504030c0c504b4353372043657274203102147bdeddd2444cd1cdfe5c41a8102c89b7df2e6cbf300d06096086480165030402010500300d06092a864886f70d0101010500048201005becd87195c1deff90c24c91269b55b3f069bc225c326c314c1a51786ffe14c830be4e4bc73cba36c97677b44168279be91e7cdf7c19386ae21862719d13a3a0fff0803d460962f2cda8371484873252c3d7054db8143e2b081a3816ed0804ca5099ae5fece83d5c2c3783b1988b4b46dc94e55587a107ea1546bf22d28a097f652a4066dc2965269069af2f5176bb8ce9ca6d11f96757f03204f756703587d00ad424796c92fc7aeb6f494431999eda30990e4f5773632ed258fe0276673599da6fce35cdad7726a0bb024cad996b88e0cb98854ceb5c0b6ec748d9f9ce6a6cd437858bacb814618a272ff3a415c6e07f3db0988777fdec845a97bf7d102dd030820173020101304c3034310b3009060355040613024e4c310e300c060355040a0c05504b4353373115301306035504030c0c504b435337204365727420320214564d554025af599e327079b2720ef00df37cfb7c300d06096086480165030402010500300d06092a864886f70d010101050004820100046098dc5f2b99e3bc2ed6642d7f0a61efabc15c38c76333bccceeee369a4f4a5bdda8ea59264124e429f08632683ddba17bbf262d82b6befa3b4e1480376a8c7f3c7d7e2a6779bbf18262aa857de8c20a12b6a2ce8e4d7f31dd1b195392cf6185afce34afe05896057b36e9b171b6c67ed7c2286cbfa83ff8a167c7bc7109aee7d7e1909bd384fbfc61938efca51c8993c71db317730f16e7e776867ae4fdc562d6f15de585e7b94ef496a3676367a2cbaab7b636648b0076bad5cdf1e09740ec6a451bff534efa21509f3ba77b8101b91ea7e55ddbfe1401517067d7b01a2a0879f0885c894a87cfb68c4d7ee890604881aeb97c22d1f337ef923e035a640030820173020101304c3034310b3009060355040613024e4c310e300c060355040a0c05504b4353373115301306035504030c0c504b43533720436572742033021462477298759e8e04718ae563155f3523cfb84cdb300d06096086480165030402010500300d06092a864886f70d0101010500048201016d2cbb37fd12957e5a7480ce0435e8ef6077def08ff270844de2516a4742f211d8c74690bc0948e08a296abba9285f6bb305b95b7f9408ce44e83880c719444672ec99746ba78cc4bde475319d01bde77c49d58d16d3b2e91c2e61e8303ca3d7eda3797fd8b35ca72bb14b15a24b56bb70dc13484565808110ff5db58c56f7a0435607e3c352fbf4f55106f2980fd3cd42397dbf7137ee7f1e32cd80a3b7ab12b46c169220278d7717b78a3c45d6395a130a8b58841cbc290e4f817de3a4fe16ecd077ca33a0aa25e235cc7f6655a80ba8aeec87905bb2a75459b7bcc5a133f2993493b41ffcf63cd7a391e3e6f78094ca442c80144403cb0a5f00bfc61ae880"
+
+PKCS7 Signed Data Verify Pass: zero-len data #795.0
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_zerolendata_detached-2.der":"../framework/data_files/pkcs7-rsa-sha256-leaf-1.der":"../framework/data_files/pkcs7_zerolendata.bin":0:0:0
+
+PKCS7 Signed Data Verify Fail: zero-len data #795.1
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_zerolendata_detached-2.der":"../framework/data_files/pkcs7-rsa-sha256-leaf-3.der":"../framework/data_files/pkcs7_zerolendata.bin":0:0:MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND
+
+PKCS7 Signed Data Verify Pass: Embedded leaf & Intermediate and Trusted Root cert #796.0
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256-2.der":"../framework/data_files/pkcs7-rsa-sha256-root-ca-1.pem":"../framework/data_files/pkcs7_data.bin":0:1:0
+
+PKCS7 Signed Data Verify Fail: Embedded leaf & Intermediate cert, chain check #796.1
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256-2.der":"NULL":"../framework/data_files/pkcs7_data.bin":0:1:MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA
+
+PKCS7 Signed Data Verify Fail: Invalid Root CA, chain check #796.2
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY:MBEDTLS_PEM_PARSE_C
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256-2.der":"../framework/data_files/pkcs7-rsa-sha256-root-ca-2.pem":"../framework/data_files/pkcs7_data.bin":0:1:MBEDTLS_ERR_PKCS7_CERT_VERIFY_FAILED
+
+PKCS7 Signed Data Verify Fail: Embedded leaf signer cert #797.0
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256.der":"NULL":"../framework/data_files/pkcs7_data.bin":0:0:MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA
+
+PKCS7 Signed Data Verify Pass: Trusted CA cert, chain check  #797.1
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256.der":"../framework/data_files/pkcs7-rsa-sha256-int-ca-1.der":"../framework/data_files/pkcs7_data.bin":0:1:0
+
+PKCS7 Signed Data Verify Fail: Invalid CA cert, chain check #797.2
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256.der":"../framework/data_files/pkcs7-rsa-sha256-int-ca-3.der":"../framework/data_files/pkcs7_data.bin":0:1:MBEDTLS_ERR_PKCS7_CERT_VERIFY_FAILED
+
+PKCS7 signed data verify Fail: NULL PKCS7 input #798.0
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"NULL":"../framework/data_files/pkcs7-rsa-sha256-1.pem":"../framework/data_files/pkcs7_data.bin":0:1:MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA
+
+PKCS7 signed data verify Fail: data is NULL #798.1
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256.der":"NULL":"NULL":0:1:MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA
+
+PKCS7 signed data verify Fail: Invalid chain_check input #798.2
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256.der":"NULL":"../framework/data_files/pkcs7_data.bin":0:2:MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA
+
+PKCS7 Signed Data Verify Pass: Trusted signer cert #799.0
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_without_cert.der":"../framework/data_files/pkcs7-rsa-sha256-leaf-1.der":"../framework/data_files/pkcs7_data.bin":0:0:0
+
+PKCS7 Signed Data Verify Fail: Trusted signer cert chain, chain check #799.1
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY:MBEDTLS_PEM_PARSE_C
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_without_cert.der":"../framework/data_files/pkcs7-rsa-sha256-leaf-1.der":"../framework/data_files/pkcs7_data.bin":0:1:MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND
+
+PKCS7 Signed Data Verify Pass: Multiple signers, chain check  #800.0
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256-3.der":"../framework/data_files/pkcs7-rsa-sha256-ca-chain.pem":"../framework/data_files/pkcs7_data.bin":0:1:0
+
+PKCS7 Signed Data Verify Pass: Multiple signers,Trusted Root cert, chain check #800.1
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_multi_cert_sha256.der":"../framework/data_files/pkcs7-rsa-sha256-root-ca-1.pem":"../framework/data_files/pkcs7_data.bin":0:1:0
+
+PKCS7 Signed Data Verify Pass: Multiple signers, chain check #800.2
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256-3.der":"../framework/data_files/pkcs7-rsa-sha256-int-ca-2.der":"../framework/data_files/pkcs7_data.bin":0:1:0
+
+PKCS7 Signed Data Verify Fail: Multiple signers, Invalid CA cert  #800.3
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256-3.der":"../framework/data_files/pkcs7-rsa-sha256-int-ca-3.der":"../framework/data_files/pkcs7_data.bin":0:1:MBEDTLS_ERR_PKCS7_CERT_VERIFY_FAILED
+
+PKCS7 Signed Data Hash Verify Pass: Trusted CA chain, chain check #801.0
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256.der":"../framework/data_files/pkcs7-rsa-sha256-ca-chain.pem":"../framework/data_files/pkcs7_data.bin":MBEDTLS_MD_SHA256:1:0
+
+PKCS7 Signed Data Hash Verify Fail: Invalid data input, chain check #801.1
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256.der":"../framework/data_files/pkcs7-rsa-sha256-ca-chain.pem":"../framework/data_files/pkcs7_data_1.bin":MBEDTLS_MD_SHA256:1:MBEDTLS_ERR_PKCS7_VERIFY_FAIL
+
+PKCS7 Signed Data Hash Verify Fail: Different Hash Algorithm #801.2
+depends_on:PSA_WANT_ALG_SHA_256:PSA_WANT_ALG_SHA_512:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256.der":"../framework/data_files/pkcs7-rsa-sha256-ca-chain.pem":"../framework/data_files/pkcs7_data.bin":MBEDTLS_MD_SHA512:1:MBEDTLS_ERR_PKCS7_VERIFY_FAIL
+
+PKCS7 Signed Data Verify Fail: Expired Certificate #802
+depends_on:PSA_WANT_ALG_SHA_256:MBEDTLS_HAVE_TIME_DATE
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_without_cert.der":"../framework/data_files/pkcs7-rsa-expired-2.der":"../framework/data_files/pkcs7_data.bin":0:0:MBEDTLS_ERR_PKCS7_CERT_DATE_INVALID
+
+PKCS7 Signed Data Verify Fail: Invalid Certificate KeyUsage #803
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_data_invalid_KU_cert.der":"../framework/data_files/pkcs7-rsa-sha256-invalid-leaf.der":"../framework/data_files/pkcs7_data.bin":0:0:MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND
+
+PKCS7 Signed Data Verify Pass: Root-Signed Leaf Certificate, chain check #804
+depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
+pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256-4.der":"../framework/data_files/pkcs7-rsa-sha256-root-ca-1.pem":"../framework/data_files/pkcs7_data.bin":0:1:0
diff --git a/tests/suites/test_suite_pkcs7.function b/tests/suites/test_suite_pkcs7.function
index 3bd7595b96..e5d2b694c7 100644
--- a/tests/suites/test_suite_pkcs7.function
+++ b/tests/suites/test_suite_pkcs7.function
@@ -227,3 +227,94 @@ exit:
     USE_PSA_DONE();
 }
 /* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CRT_PARSE_C:PSA_HAVE_ALG_SOME_RSA_VERIFY */
+void pkcs7_verify_ext(char *pkcs7_file, char *certs_file, char *input_file,
+                      int do_hash_alg, int chain_check, int expect_ret)
+{
+    unsigned char *pkcs7_buf = NULL;
+    unsigned char *data = NULL;
+    unsigned char *hash = NULL;
+    size_t pkcs7_len = 0;
+    size_t datalen = 0;
+    size_t hashlen = 0;
+    int ret;
+    FILE *file = NULL;
+    struct stat st;
+    const mbedtls_md_info_t *md_info = NULL;
+
+    mbedtls_pkcs7 pkcs7;
+    mbedtls_x509_crt certs;
+
+    USE_PSA_INIT();
+
+    mbedtls_pkcs7_init(&pkcs7);
+    mbedtls_x509_crt_init(&certs);
+
+    /* Load PKCS7 */
+    if (strcmp(pkcs7_file, "NULL") != 0) {
+        ret = mbedtls_pk_load_file(pkcs7_file, &pkcs7_buf, &pkcs7_len);
+        TEST_EQUAL(ret, 0);
+
+        ret = mbedtls_pkcs7_parse_der(&pkcs7, pkcs7_buf, pkcs7_len);
+        TEST_EQUAL(ret, MBEDTLS_PKCS7_SIGNED_DATA);
+    }
+
+    /* Load certs */
+    if (strcmp(certs_file, "NULL") != 0) {
+        ret = mbedtls_x509_crt_parse_file(&certs, certs_file);
+        TEST_EQUAL(ret, 0);
+    }
+
+    /* Load data */
+    if (strcmp(input_file, "NULL") != 0) {
+        ret = stat(input_file, &st);
+        TEST_EQUAL(ret, 0);
+
+        datalen = st.st_size;
+        TEST_CALLOC(data, datalen == 0 ? 1 : datalen);
+
+        file = fopen(input_file, "rb");
+        TEST_ASSERT(file != NULL);
+        TEST_EQUAL(fread(data, 1, datalen, file), datalen);
+        fclose(file);
+        file = NULL;
+    }
+
+    if (do_hash_alg) {
+        md_info = mbedtls_md_info_from_type((mbedtls_md_type_t) do_hash_alg);
+        TEST_ASSERT(md_info != NULL);
+
+        hashlen = mbedtls_md_get_size(md_info);
+        TEST_CALLOC(hash, hashlen);
+
+        if (data != NULL && datalen != 0) {
+            ret = mbedtls_md(md_info, data, datalen, hash);
+            TEST_EQUAL(ret, 0);
+        }
+
+        ret = mbedtls_pkcs7_signed_hash_verify_ext(
+            strcmp(pkcs7_file, "NULL") ? &pkcs7 : NULL,
+            strcmp(certs_file, "NULL") ? &certs : NULL,  hash, hashlen,
+            chain_check);
+    } else {
+        ret = mbedtls_pkcs7_signed_data_verify_ext(
+            strcmp(pkcs7_file, "NULL") ? &pkcs7 : NULL,
+            strcmp(certs_file, "NULL") ? &certs : NULL, data, datalen,
+            chain_check);
+    }
+
+    TEST_EQUAL(ret, expect_ret);
+
+exit:
+    if (file != NULL) {
+        fclose(file);
+    }
+    mbedtls_free(hash);
+    mbedtls_free(data);
+    mbedtls_x509_crt_free(&certs);
+    mbedtls_pkcs7_free(&pkcs7);
+    mbedtls_free(pkcs7_buf);
+    USE_PSA_DONE();
+}
+/* END_CASE */

From 402e80b575fc4767644847936c7d1ba7243762a6 Mon Sep 17 00:00:00 2001
From: Sridhar Markonda <sridharm@linux.ibm.com>
Date: Thu, 27 Aug 2026 11:13:09 -0500
Subject: [PATCH 5/9] pkcs7: add APIs for embedded certificate handling

Add APIs to retrieve the number of certificates embedded in a
PKCS#7 SignedData structure and to extract the embedded certificates
into an mbedtls_x509_crt chain owned by the caller.

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
---
 include/mbedtls/pkcs7.h | 30 ++++++++++++++++++++++++++
 library/pkcs7.c         | 48 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 78 insertions(+)

diff --git a/include/mbedtls/pkcs7.h b/include/mbedtls/pkcs7.h
index 9d89158bc2..29cdcdfe68 100644
--- a/include/mbedtls/pkcs7.h
+++ b/include/mbedtls/pkcs7.h
@@ -316,6 +316,36 @@ int mbedtls_pkcs7_signed_hash_verify_ext(const mbedtls_pkcs7 *pkcs7,
                                          const size_t hashlen,
                                          const int use_pkcs7_leaf);
 
+/**
+ * \brief        Return the number of certificates embedded in a PKCS #7 SignedData
+ *               structure.
+ *
+ * \param pkcs7  PKCS #7 structure containing signature and certificates.
+ *
+ * \return       Number of embedded certificates (>= 0), or
+ *               #MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA if \p pkcs7 is NULL.
+ */
+int mbedtls_pkcs7_get_cert_count(const mbedtls_pkcs7 *pkcs7);
+
+/**
+ * \brief           Extract embedded certificates from PKCS#7 SignedData.
+ *
+ * \details         Creates a new certificate chain by parsing the DER-encoded
+ *                  certificates embedded in the PKCS#7 structure. The caller
+ *                  is responsible for freeing the returned certificate chain.
+ *
+ * \param pkcs7     PKCS#7 structure containing embedded certificates.
+ * \param out_certs On success, pointer to newly allocated certificate chain.
+ *                  Caller must free with mbedtls_x509_crt_free() and mbedtls_free().
+ *
+ * \return          0 on success,
+ *                  #MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA if \p pkcs7 is NULL,
+ *                  \p out_certs is NULL, or no certificates are embedded,
+ *                  or a negative error code on failure.
+ */
+int mbedtls_pkcs7_get_certs(const mbedtls_pkcs7 *pkcs7,
+			    mbedtls_x509_crt **out_certs);
+
 /**
  * \brief          Unallocate all PKCS #7 data and zeroize the memory.
  *                 It doesn't free \p pkcs7 itself. This should be done by the caller.
diff --git a/library/pkcs7.c b/library/pkcs7.c
index 7f58569e4d..9a4254c43e 100644
--- a/library/pkcs7.c
+++ b/library/pkcs7.c
@@ -1176,6 +1176,54 @@ int mbedtls_pkcs7_signed_hash_verify_ext(const mbedtls_pkcs7 *pkcs7,
                                              1, use_pkcs7_leaf);
 }
 
+int mbedtls_pkcs7_get_cert_count(const mbedtls_pkcs7 *pkcs7)
+{
+    if (pkcs7 == NULL) {
+        return MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA;
+    }
+
+    return pkcs7->signed_data.no_of_certs;
+}
+
+int mbedtls_pkcs7_get_certs(const mbedtls_pkcs7 *pkcs7,
+                            mbedtls_x509_crt **out_certs)
+{
+    const mbedtls_pkcs7_cert *embedded_cert;
+    mbedtls_x509_crt *cert_chain = NULL;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
+    if (pkcs7 == NULL || out_certs == NULL) {
+        return MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA;
+    }
+
+    *out_certs = NULL;
+    if (pkcs7->signed_data.no_of_certs == 0) {
+        return MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA;
+    }
+
+    cert_chain = (mbedtls_x509_crt *) mbedtls_calloc(1, sizeof(mbedtls_x509_crt));
+    if (cert_chain == NULL) {
+        return MBEDTLS_ERR_PKCS7_ALLOC_FAILED;
+    }
+
+    mbedtls_x509_crt_init(cert_chain);
+
+    for (embedded_cert = pkcs7->signed_data.certs; embedded_cert != NULL;
+         embedded_cert = embedded_cert->next) {
+        ret = mbedtls_x509_crt_parse_der(cert_chain, embedded_cert->cert.raw.p,
+                                         embedded_cert->cert.raw.len);
+        if (ret != 0) {
+            mbedtls_x509_crt_free(cert_chain);
+            mbedtls_free(cert_chain);
+            return ret;
+        }
+    }
+
+    *out_certs = cert_chain;
+
+    return 0;
+}
+
 /*
  * Unallocate all pkcs7 data
  */

From cdb531ffe3f17de7887b51a93c88daca62f33bd7 Mon Sep 17 00:00:00 2001
From: Sridhar Markonda <sridharm@linux.ibm.com>
Date: Thu, 27 Aug 2026 11:28:25 -0500
Subject: [PATCH 6/9] tests: Add tests for PKCS#7 embedded certificate APIs

The new tests validate certificate count retrieval and embedded
certificate extraction.

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
---
 tests/suites/test_suite_pkcs7.data     | 28 +++++++++
 tests/suites/test_suite_pkcs7.function | 82 ++++++++++++++++++++++++++
 2 files changed, 110 insertions(+)

diff --git a/tests/suites/test_suite_pkcs7.data b/tests/suites/test_suite_pkcs7.data
index 74d1947e37..2717133b37 100644
--- a/tests/suites/test_suite_pkcs7.data
+++ b/tests/suites/test_suite_pkcs7.data
@@ -3363,3 +3363,31 @@ pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_data_invalid_KU_cert.der"
 PKCS7 Signed Data Verify Pass: Root-Signed Leaf Certificate, chain check #804
 depends_on:PSA_WANT_ALG_SHA_256:PSA_HAVE_ALG_RSA_PKCS1V15_VERIFY
 pkcs7_verify_ext:"../framework/data_files/pkcs7_signed_cert_sha256-4.der":"../framework/data_files/pkcs7-rsa-sha256-root-ca-1.pem":"../framework/data_files/pkcs7_data.bin":0:1:0
+
+PKCS7 get embedded certs: SignedData with cert #805.0
+depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CRT_PARSE_C
+pkcs7_get_certs:"../framework/data_files/pkcs7_signed_cert_sha256.der":0
+
+PKCS7 get embedded certs: SignedData with multiple certs #805.1
+depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CRT_PARSE_C
+pkcs7_get_certs:"../framework/data_files/pkcs7_signed_multi_cert_sha256.der":0
+
+PKCS7 get embedded certs: SignedData without certs #805.2
+depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CRT_PARSE_C
+pkcs7_get_certs:"../framework/data_files/pkcs7_signed_without_cert.der":MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA
+
+PKCS7 embedded cert count: SignedData with certificates #806.0
+depends_on:MBEDTLS_FS_IO
+pkcs7_get_cert_count:"../framework/data_files/pkcs7_signed_cert_sha256.der":1
+
+PKCS7 embedded cert count: SignedData without certificates #806.1
+depends_on:MBEDTLS_FS_IO
+pkcs7_get_cert_count:"../framework/data_files/pkcs7_signed_without_cert.der":0
+
+PKCS7 embedded cert count: SignedData with multiple certs #806.2
+depends_on:MBEDTLS_FS_IO
+pkcs7_get_cert_count:"../framework/data_files/pkcs7_signed_multi_cert_sha256.der":4
+
+PKCS7 embedded cert count: NULL pkcs7 returns error #806.3
+depends_on:MBEDTLS_FS_IO
+pkcs7_get_cert_count:"NULL":MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA
diff --git a/tests/suites/test_suite_pkcs7.function b/tests/suites/test_suite_pkcs7.function
index e5d2b694c7..3e319e4f7b 100644
--- a/tests/suites/test_suite_pkcs7.function
+++ b/tests/suites/test_suite_pkcs7.function
@@ -318,3 +318,85 @@ exit:
     USE_PSA_DONE();
 }
 /* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CRT_PARSE_C */
+void pkcs7_get_certs(char *pkcs7_file, int expected_ret)
+{
+    unsigned char *pkcs7_buf = NULL;
+    size_t buflen;
+    int ret;
+    char info[512];
+
+    mbedtls_pkcs7 pkcs7;
+    mbedtls_x509_crt *certs = NULL;
+
+    USE_PSA_INIT();
+
+    mbedtls_pkcs7_init(&pkcs7);
+
+    ret = mbedtls_pk_load_file(pkcs7_file, &pkcs7_buf, &buflen);
+    TEST_EQUAL(ret, 0);
+
+    ret = mbedtls_pkcs7_parse_der(&pkcs7, pkcs7_buf, buflen);
+    TEST_EQUAL(ret, MBEDTLS_PKCS7_SIGNED_DATA);
+
+    ret = mbedtls_pkcs7_get_certs(&pkcs7, &certs);
+    TEST_EQUAL(ret, expected_ret);
+
+    if (expected_ret == 0) {
+        TEST_ASSERT(certs != NULL);
+
+        /* deep copy check */
+        mbedtls_pkcs7_free(&pkcs7);
+        mbedtls_x509_crt_info(info, sizeof(info), "  ", certs);
+        TEST_ASSERT(strlen(info) > 0);
+
+        mbedtls_x509_crt_free(certs);
+        mbedtls_free(certs);
+        certs = NULL;
+    } else {
+        TEST_EQUAL(certs, NULL);
+    }
+
+exit:
+    if (certs != NULL) {
+        mbedtls_x509_crt_free(certs);
+        mbedtls_free(certs);
+    }
+    mbedtls_free(pkcs7_buf);
+    mbedtls_pkcs7_free(&pkcs7);
+    USE_PSA_DONE();
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_FS_IO:MBEDTLS_PKCS7_C */
+void pkcs7_get_cert_count(char *pkcs7_file, int expected)
+{
+    int ret;
+    mbedtls_pkcs7 pkcs7;
+    unsigned char *buf = NULL;
+    size_t len = 0;
+
+    USE_PSA_INIT();
+
+    mbedtls_pkcs7_init(&pkcs7);
+
+    if (strcmp(pkcs7_file, "NULL") != 0) {
+        ret = mbedtls_pk_load_file(pkcs7_file, &buf, &len);
+        TEST_EQUAL(ret, 0);
+
+        ret = mbedtls_pkcs7_parse_der(&pkcs7, buf, len);
+        TEST_EQUAL(ret, MBEDTLS_PKCS7_SIGNED_DATA);
+    }
+
+    ret = mbedtls_pkcs7_get_cert_count(
+        (strcmp(pkcs7_file, "NULL") != 0) ? &pkcs7 : NULL);
+
+    TEST_EQUAL(ret, expected);
+
+exit:
+    mbedtls_pkcs7_free(&pkcs7);
+    mbedtls_free(buf);
+    USE_PSA_DONE();
+}
+/* END_CASE */

From a5ef02924f7f46632041abdf61b2c71f9f0bf67c Mon Sep 17 00:00:00 2001
From: Sridhar Markonda <sridharm@linux.ibm.com>
Date: Fri, 28 Aug 2026 09:41:30 -0500
Subject: [PATCH 7/9] Changelog: add PKCS#7 API and feature entries

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
---
 ChangeLog | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 76d65c6ac2..729026f979 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,33 @@
 Mbed TLS ChangeLog (Sorted per branch, date)
 
+= Mbed TLS x.x.x branch released xxxx-xx-xx
+
+API changes
+   * Add the public type mbedtls_pkcs7_cert and the error codes
+     MBEDTLS_ERR_PKCS7_CERT_VERIFY_FAILED and
+     MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND.
+
+   * Add the APIs mbedtls_pkcs7_signed_data_verify_ext(),
+     mbedtls_pkcs7_signed_hash_verify_ext(),
+     mbedtls_pkcs7_get_cert_count(), and mbedtls_pkcs7_get_certs().
+
+   * Update mbedtls_pkcs7_signed_data_verify() and
+     mbedtls_pkcs7_signed_hash_verify() to accept a const
+     mbedtls_pkcs7 pointer.
+
+   * mbedtls_pkcs7_signed_data_verify() and mbedtls_pkcs7_signed_hash_verify()
+     now returns MBEDTLS_ERR_PKCS7_SIGNER_CERT_NOT_FOUND when the supplied
+     certificate does not match the signer certificate.
+
+Features
+   * Add support for multiple certificates embedded in PKCS #7
+     SignedData structures.
+
+   * Add support for PKCS #7 signature verification using either signer
+     certificates embedded in the PKCS #7 structure or certificates
+     supplied by the application. Certificate chain validation for
+     PKCS #7 embedded signer certificates is also supported.
+
 = Mbed TLS 4.2.0 branch released 2026-07-07
 
 Features

From abd4720cfe81040a74a5a15bcbfef26c5cb85b09 Mon Sep 17 00:00:00 2001
From: Sridhar Markonda <sridharm@linux.ibm.com>
Date: Thu, 3 Sep 2026 03:46:40 -0500
Subject: [PATCH 8/9] tests: fix pointer comparison in PKCS7 tests

Replace TEST_EQUAL with TEST_ASSERT for pointer comparison to
avoid -Werror=pointer-to-int-cast failures on 32-bit targets.

Fixes MinGW CI failure.

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
---
 tests/suites/test_suite_pkcs7.function | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/suites/test_suite_pkcs7.function b/tests/suites/test_suite_pkcs7.function
index 3e319e4f7b..b66a54ae7c 100644
--- a/tests/suites/test_suite_pkcs7.function
+++ b/tests/suites/test_suite_pkcs7.function
@@ -355,7 +355,7 @@ void pkcs7_get_certs(char *pkcs7_file, int expected_ret)
         mbedtls_free(certs);
         certs = NULL;
     } else {
-        TEST_EQUAL(certs, NULL);
+        TEST_ASSERT(certs == NULL);
     }
 
 exit:

From e1c2286142e179d786af37083b82ead11fc7d9a3 Mon Sep 17 00:00:00 2001
From: Sridhar Markonda <sridharm@linux.ibm.com>
Date: Thu, 3 Sep 2026 03:50:47 -0500
Subject: [PATCH 9/9] pkcs7: fix indentation

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
---
 include/mbedtls/pkcs7.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/mbedtls/pkcs7.h b/include/mbedtls/pkcs7.h
index 29cdcdfe68..2875636039 100644
--- a/include/mbedtls/pkcs7.h
+++ b/include/mbedtls/pkcs7.h
@@ -344,7 +344,7 @@ int mbedtls_pkcs7_get_cert_count(const mbedtls_pkcs7 *pkcs7);
  *                  or a negative error code on failure.
  */
 int mbedtls_pkcs7_get_certs(const mbedtls_pkcs7 *pkcs7,
-			    mbedtls_x509_crt **out_certs);
+                            mbedtls_x509_crt **out_certs);
 
 /**
  * \brief          Unallocate all PKCS #7 data and zeroize the memory.