Merge pull request #6922 from mprse/csr_v3

Parsing v3 extensions from a CSR - v.2
diff --git a/ChangeLog.d/csr_v3_extensions.txt b/ChangeLog.d/csr_v3_extensions.txt
new file mode 100644
index 0000000..9274017
--- /dev/null
+++ b/ChangeLog.d/csr_v3_extensions.txt
@@ -0,0 +1,3 @@
+Features
+   * Add parsing of V3 extensions (key usage, Netscape cert-type,
+     Subject Alternative Names) in x509 Certificate Sign Requests.
diff --git a/include/mbedtls/x509.h b/include/mbedtls/x509.h
index 52fadad..aa1cd08 100644
--- a/include/mbedtls/x509.h
+++ b/include/mbedtls/x509.h
@@ -148,7 +148,7 @@
 
 /*
  * X.509 v3 Key Usage Extension flags
- * Reminder: update x509_info_key_usage() when adding new flags.
+ * Reminder: update mbedtls_x509_info_key_usage() when adding new flags.
  */
 #define MBEDTLS_X509_KU_DIGITAL_SIGNATURE            (0x80)  /* bit 0 */
 #define MBEDTLS_X509_KU_NON_REPUDIATION              (0x40)  /* bit 1 */
@@ -250,6 +250,56 @@
 }
 mbedtls_x509_time;
 
+/**
+ * From RFC 5280 section 4.2.1.6:
+ * OtherName ::= SEQUENCE {
+ *      type-id    OBJECT IDENTIFIER,
+ *      value      [0] EXPLICIT ANY DEFINED BY type-id }
+ *
+ * Future versions of the library may add new fields to this structure or
+ * to its embedded union and structure.
+ */
+typedef struct mbedtls_x509_san_other_name {
+    /**
+     * The type_id is an OID as defined in RFC 5280.
+     * To check the value of the type id, you should use
+     * \p MBEDTLS_OID_CMP with a known OID mbedtls_x509_buf.
+     */
+    mbedtls_x509_buf type_id;                   /**< The type id. */
+    union {
+        /**
+         * From RFC 4108 section 5:
+         * HardwareModuleName ::= SEQUENCE {
+         *                         hwType OBJECT IDENTIFIER,
+         *                         hwSerialNum OCTET STRING }
+         */
+        struct {
+            mbedtls_x509_buf oid;               /**< The object identifier. */
+            mbedtls_x509_buf val;               /**< The named value. */
+        }
+        hardware_module_name;
+    }
+    value;
+}
+mbedtls_x509_san_other_name;
+
+/**
+ * A structure for holding the parsed Subject Alternative Name,
+ * according to type.
+ *
+ * Future versions of the library may add new fields to this structure or
+ * to its embedded union and structure.
+ */
+typedef struct mbedtls_x509_subject_alternative_name {
+    int type;                              /**< The SAN type, value of MBEDTLS_X509_SAN_XXX. */
+    union {
+        mbedtls_x509_san_other_name other_name; /**< The otherName supported type. */
+        mbedtls_x509_buf   unstructured_name; /**< The buffer for the un constructed types. Only dnsName currently supported */
+    }
+    san; /**< A union of the supported SAN types */
+}
+mbedtls_x509_subject_alternative_name;
+
 /** \} name Structures for parsing X.509 certificates, CRLs and CSRs */
 
 /**
@@ -326,6 +376,36 @@
  */
 int mbedtls_x509_time_is_future(const mbedtls_x509_time *from);
 
+/**
+ * \brief          This function parses an item in the SubjectAlternativeNames
+ *                 extension.
+ *
+ * \param san_buf  The buffer holding the raw data item of the subject
+ *                 alternative name.
+ * \param san      The target structure to populate with the parsed presentation
+ *                 of the subject alternative name encoded in \p san_raw.
+ *
+ * \note           Only "dnsName" and "otherName" of type hardware_module_name
+ *                 as defined in RFC 4180 is supported.
+ *
+ * \note           This function should be called on a single raw data of
+ *                 subject alternative name. For example, after successful
+ *                 certificate parsing, one must iterate on every item in the
+ *                 \p crt->subject_alt_names sequence, and pass it to
+ *                 this function.
+ *
+ * \warning        The target structure contains pointers to the raw data of the
+ *                 parsed certificate, and its lifetime is restricted by the
+ *                 lifetime of the certificate.
+ *
+ * \return         \c 0 on success
+ * \return         #MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE for an unsupported
+ *                 SAN type.
+ * \return         Another negative value for any other failure.
+ */
+int mbedtls_x509_parse_subject_alt_name(const mbedtls_x509_buf *san_buf,
+                                        mbedtls_x509_subject_alternative_name *san);
+
 /** \} addtogroup x509_module */
 
 /*
@@ -370,6 +450,23 @@
 int mbedtls_x509_write_sig(unsigned char **p, unsigned char *start,
                            const char *oid, size_t oid_len,
                            unsigned char *sig, size_t size);
+int mbedtls_x509_get_ns_cert_type(unsigned char **p,
+                                  const unsigned char *end,
+                                  unsigned char *ns_cert_type);
+int mbedtls_x509_get_key_usage(unsigned char **p,
+                               const unsigned char *end,
+                               unsigned int *key_usage);
+int mbedtls_x509_get_subject_alt_name(unsigned char **p,
+                                      const unsigned char *end,
+                                      mbedtls_x509_sequence *subject_alt_name);
+int mbedtls_x509_info_subject_alt_name(char **buf, size_t *size,
+                                       const mbedtls_x509_sequence
+                                       *subject_alt_name,
+                                       const char *prefix);
+int mbedtls_x509_info_cert_type(char **buf, size_t *size,
+                                unsigned char ns_cert_type);
+int mbedtls_x509_info_key_usage(char **buf, size_t *size,
+                                unsigned int key_usage);
 
 #define MBEDTLS_X509_SAFE_SNPRINTF                          \
     do {                                                    \
diff --git a/include/mbedtls/x509_crt.h b/include/mbedtls/x509_crt.h
index 7c3a625..187e60a 100644
--- a/include/mbedtls/x509_crt.h
+++ b/include/mbedtls/x509_crt.h
@@ -103,56 +103,6 @@
 mbedtls_x509_crt;
 
 /**
- * From RFC 5280 section 4.2.1.6:
- * OtherName ::= SEQUENCE {
- *      type-id    OBJECT IDENTIFIER,
- *      value      [0] EXPLICIT ANY DEFINED BY type-id }
- *
- * Future versions of the library may add new fields to this structure or
- * to its embedded union and structure.
- */
-typedef struct mbedtls_x509_san_other_name {
-    /**
-     * The type_id is an OID as defined in RFC 5280.
-     * To check the value of the type id, you should use
-     * \p MBEDTLS_OID_CMP with a known OID mbedtls_x509_buf.
-     */
-    mbedtls_x509_buf type_id;                   /**< The type id. */
-    union {
-        /**
-         * From RFC 4108 section 5:
-         * HardwareModuleName ::= SEQUENCE {
-         *                         hwType OBJECT IDENTIFIER,
-         *                         hwSerialNum OCTET STRING }
-         */
-        struct {
-            mbedtls_x509_buf oid;               /**< The object identifier. */
-            mbedtls_x509_buf val;               /**< The named value. */
-        }
-        hardware_module_name;
-    }
-    value;
-}
-mbedtls_x509_san_other_name;
-
-/**
- * A structure for holding the parsed Subject Alternative Name,
- * according to type.
- *
- * Future versions of the library may add new fields to this structure or
- * to its embedded union and structure.
- */
-typedef struct mbedtls_x509_subject_alternative_name {
-    int type;                              /**< The SAN type, value of MBEDTLS_X509_SAN_XXX. */
-    union {
-        mbedtls_x509_san_other_name other_name; /**< The otherName supported type. */
-        mbedtls_x509_buf   unstructured_name; /**< The buffer for the un constructed types. Only dnsName currently supported */
-    }
-    san; /**< A union of the supported SAN types */
-}
-mbedtls_x509_subject_alternative_name;
-
-/**
  * Build flag from an algorithm/curve identifier (pk, md, ecp)
  * Since 0 is always XXX_NONE, ignore it.
  */
@@ -590,36 +540,6 @@
 int mbedtls_x509_crt_parse_path(mbedtls_x509_crt *chain, const char *path);
 
 #endif /* MBEDTLS_FS_IO */
-/**
- * \brief          This function parses an item in the SubjectAlternativeNames
- *                 extension.
- *
- * \param san_buf  The buffer holding the raw data item of the subject
- *                 alternative name.
- * \param san      The target structure to populate with the parsed presentation
- *                 of the subject alternative name encoded in \p san_raw.
- *
- * \note           Only "dnsName" and "otherName" of type hardware_module_name
- *                 as defined in RFC 4180 is supported.
- *
- * \note           This function should be called on a single raw data of
- *                 subject alternative name. For example, after successful
- *                 certificate parsing, one must iterate on every item in the
- *                 \p crt->subject_alt_names sequence, and pass it to
- *                 this function.
- *
- * \warning        The target structure contains pointers to the raw data of the
- *                 parsed certificate, and its lifetime is restricted by the
- *                 lifetime of the certificate.
- *
- * \return         \c 0 on success
- * \return         #MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE for an unsupported
- *                 SAN type.
- * \return         Another negative value for any other failure.
- */
-int mbedtls_x509_parse_subject_alt_name(const mbedtls_x509_buf *san_buf,
-                                        mbedtls_x509_subject_alternative_name *san);
-
 #if !defined(MBEDTLS_X509_REMOVE_INFO)
 /**
  * \brief          Returns an informational string about the
diff --git a/include/mbedtls/x509_csr.h b/include/mbedtls/x509_csr.h
index 50998c4..0c204be 100644
--- a/include/mbedtls/x509_csr.h
+++ b/include/mbedtls/x509_csr.h
@@ -58,6 +58,12 @@
 
     mbedtls_pk_context pk;          /**< Container for the public key context. */
 
+    unsigned int key_usage;     /**< Optional key usage extension value: See the values in x509.h */
+    unsigned char ns_cert_type; /**< Optional Netscape certificate type extension value: See the values in x509.h */
+    mbedtls_x509_sequence subject_alt_names;    /**< Optional list of raw entries of Subject Alternative Names extension (currently only dNSName and OtherName are listed). */
+
+    int MBEDTLS_PRIVATE(ext_types);              /**< Bit string containing detected and parsed extensions */
+
     mbedtls_x509_buf sig_oid;
     mbedtls_x509_buf MBEDTLS_PRIVATE(sig);
     mbedtls_md_type_t MBEDTLS_PRIVATE(sig_md);       /**< Internal representation of the MD algorithm of the signature algorithm, e.g. MBEDTLS_MD_SHA256 */
diff --git a/library/x509.c b/library/x509.c
index 1b3701c..81e30e4 100644
--- a/library/x509.c
+++ b/library/x509.c
@@ -1107,4 +1107,489 @@
     return 0;
 }
 #endif /* MBEDTLS_HAVE_TIME_DATE */
+
+/* Common functions for parsing CRT and CSR. */
+#if defined(MBEDTLS_X509_CRT_PARSE_C) || defined(MBEDTLS_X509_CSR_PARSE_C)
+/*
+ * OtherName ::= SEQUENCE {
+ *      type-id    OBJECT IDENTIFIER,
+ *      value      [0] EXPLICIT ANY DEFINED BY type-id }
+ *
+ * HardwareModuleName ::= SEQUENCE {
+ *                           hwType OBJECT IDENTIFIER,
+ *                           hwSerialNum OCTET STRING }
+ *
+ * NOTE: we currently only parse and use otherName of type HwModuleName,
+ * as defined in RFC 4108.
+ */
+static int x509_get_other_name(const mbedtls_x509_buf *subject_alt_name,
+                               mbedtls_x509_san_other_name *other_name)
+{
+    int ret = 0;
+    size_t len;
+    unsigned char *p = subject_alt_name->p;
+    const unsigned char *end = p + subject_alt_name->len;
+    mbedtls_x509_buf cur_oid;
+
+    if ((subject_alt_name->tag &
+         (MBEDTLS_ASN1_TAG_CLASS_MASK | MBEDTLS_ASN1_TAG_VALUE_MASK)) !=
+        (MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_OTHER_NAME)) {
+        /*
+         * The given subject alternative name is not of type "othername".
+         */
+        return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
+    }
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_OID)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+    }
+
+    cur_oid.tag = MBEDTLS_ASN1_OID;
+    cur_oid.p = p;
+    cur_oid.len = len;
+
+    /*
+     * Only HwModuleName is currently supported.
+     */
+    if (MBEDTLS_OID_CMP(MBEDTLS_OID_ON_HW_MODULE_NAME, &cur_oid) != 0) {
+        return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
+    }
+
+    if (p + len >= end) {
+        mbedtls_platform_zeroize(other_name, sizeof(*other_name));
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+    p += len;
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_CONTEXT_SPECIFIC)) !=
+        0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+    }
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+    }
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OID)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+    }
+
+    other_name->value.hardware_module_name.oid.tag = MBEDTLS_ASN1_OID;
+    other_name->value.hardware_module_name.oid.p = p;
+    other_name->value.hardware_module_name.oid.len = len;
+
+    if (p + len >= end) {
+        mbedtls_platform_zeroize(other_name, sizeof(*other_name));
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+    p += len;
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_OCTET_STRING)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+    }
+
+    other_name->value.hardware_module_name.val.tag = MBEDTLS_ASN1_OCTET_STRING;
+    other_name->value.hardware_module_name.val.p = p;
+    other_name->value.hardware_module_name.val.len = len;
+    p += len;
+    if (p != end) {
+        mbedtls_platform_zeroize(other_name,
+                                 sizeof(*other_name));
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+    return 0;
+}
+
+/*
+ * SubjectAltName ::= GeneralNames
+ *
+ * GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
+ *
+ * GeneralName ::= CHOICE {
+ *      otherName                       [0]     OtherName,
+ *      rfc822Name                      [1]     IA5String,
+ *      dNSName                         [2]     IA5String,
+ *      x400Address                     [3]     ORAddress,
+ *      directoryName                   [4]     Name,
+ *      ediPartyName                    [5]     EDIPartyName,
+ *      uniformResourceIdentifier       [6]     IA5String,
+ *      iPAddress                       [7]     OCTET STRING,
+ *      registeredID                    [8]     OBJECT IDENTIFIER }
+ *
+ * OtherName ::= SEQUENCE {
+ *      type-id    OBJECT IDENTIFIER,
+ *      value      [0] EXPLICIT ANY DEFINED BY type-id }
+ *
+ * EDIPartyName ::= SEQUENCE {
+ *      nameAssigner            [0]     DirectoryString OPTIONAL,
+ *      partyName               [1]     DirectoryString }
+ *
+ * NOTE: we list all types, but only use dNSName and otherName
+ * of type HwModuleName, as defined in RFC 4108, at this point.
+ */
+int mbedtls_x509_get_subject_alt_name(unsigned char **p,
+                                      const unsigned char *end,
+                                      mbedtls_x509_sequence *subject_alt_name)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t len, tag_len;
+    mbedtls_asn1_buf *buf;
+    unsigned char tag;
+    mbedtls_asn1_sequence *cur = subject_alt_name;
+
+    /* Get main sequence tag */
+    if ((ret = mbedtls_asn1_get_tag(p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+    }
+
+    if (*p + len != end) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    while (*p < end) {
+        mbedtls_x509_subject_alternative_name dummy_san_buf;
+        memset(&dummy_san_buf, 0, sizeof(dummy_san_buf));
+
+        tag = **p;
+        (*p)++;
+        if ((ret = mbedtls_asn1_get_len(p, end, &tag_len)) != 0) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+        }
+
+        if ((tag & MBEDTLS_ASN1_TAG_CLASS_MASK) !=
+            MBEDTLS_ASN1_CONTEXT_SPECIFIC) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                     MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
+        }
+
+        /*
+         * Check that the SAN is structured correctly.
+         */
+        ret = mbedtls_x509_parse_subject_alt_name(&(cur->buf), &dummy_san_buf);
+        /*
+         * In case the extension is malformed, return an error,
+         * and clear the allocated sequences.
+         */
+        if (ret != 0 && ret != MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE) {
+            mbedtls_asn1_sequence_free(subject_alt_name->next);
+            subject_alt_name->next = NULL;
+            return ret;
+        }
+
+        /* Allocate and assign next pointer */
+        if (cur->buf.p != NULL) {
+            if (cur->next != NULL) {
+                return MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
+            }
+
+            cur->next = mbedtls_calloc(1, sizeof(mbedtls_asn1_sequence));
+
+            if (cur->next == NULL) {
+                return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                         MBEDTLS_ERR_ASN1_ALLOC_FAILED);
+            }
+
+            cur = cur->next;
+        }
+
+        buf = &(cur->buf);
+        buf->tag = tag;
+        buf->p = *p;
+        buf->len = tag_len;
+        *p += buf->len;
+    }
+
+    /* Set final sequence entry's next pointer to NULL */
+    cur->next = NULL;
+
+    if (*p != end) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    return 0;
+}
+
+int mbedtls_x509_get_ns_cert_type(unsigned char **p,
+                                  const unsigned char *end,
+                                  unsigned char *ns_cert_type)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    mbedtls_x509_bitstring bs = { 0, 0, NULL };
+
+    if ((ret = mbedtls_asn1_get_bitstring(p, end, &bs)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+    }
+
+    /* A bitstring with no flags set is still technically valid, as it will mean
+       that the certificate has no designated purpose at the time of creation. */
+    if (bs.len == 0) {
+        *ns_cert_type = 0;
+        return 0;
+    }
+
+    if (bs.len != 1) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                 MBEDTLS_ERR_ASN1_INVALID_LENGTH);
+    }
+
+    /* Get actual bitstring */
+    *ns_cert_type = *bs.p;
+    return 0;
+}
+
+int mbedtls_x509_get_key_usage(unsigned char **p,
+                               const unsigned char *end,
+                               unsigned int *key_usage)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t i;
+    mbedtls_x509_bitstring bs = { 0, 0, NULL };
+
+    if ((ret = mbedtls_asn1_get_bitstring(p, end, &bs)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+    }
+
+    /* A bitstring with no flags set is still technically valid, as it will mean
+       that the certificate has no designated purpose at the time of creation. */
+    if (bs.len == 0) {
+        *key_usage = 0;
+        return 0;
+    }
+
+    /* Get actual bitstring */
+    *key_usage = 0;
+    for (i = 0; i < bs.len && i < sizeof(unsigned int); i++) {
+        *key_usage |= (unsigned int) bs.p[i] << (8*i);
+    }
+
+    return 0;
+}
+
+int mbedtls_x509_parse_subject_alt_name(const mbedtls_x509_buf *san_buf,
+                                        mbedtls_x509_subject_alternative_name *san)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    switch (san_buf->tag &
+            (MBEDTLS_ASN1_TAG_CLASS_MASK |
+             MBEDTLS_ASN1_TAG_VALUE_MASK)) {
+        /*
+         * otherName
+         */
+        case (MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_OTHER_NAME):
+        {
+            mbedtls_x509_san_other_name other_name;
+
+            ret = x509_get_other_name(san_buf, &other_name);
+            if (ret != 0) {
+                return ret;
+            }
+
+            memset(san, 0, sizeof(mbedtls_x509_subject_alternative_name));
+            san->type = MBEDTLS_X509_SAN_OTHER_NAME;
+            memcpy(&san->san.other_name,
+                   &other_name, sizeof(other_name));
+
+        }
+        break;
+
+        /*
+         * dNSName
+         */
+        case (MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_DNS_NAME):
+        {
+            memset(san, 0, sizeof(mbedtls_x509_subject_alternative_name));
+            san->type = MBEDTLS_X509_SAN_DNS_NAME;
+
+            memcpy(&san->san.unstructured_name,
+                   san_buf, sizeof(*san_buf));
+
+        }
+        break;
+
+        /*
+         * Type not supported
+         */
+        default:
+            return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
+    }
+    return 0;
+}
+
+#if !defined(MBEDTLS_X509_REMOVE_INFO)
+int mbedtls_x509_info_subject_alt_name(char **buf, size_t *size,
+                                       const mbedtls_x509_sequence
+                                       *subject_alt_name,
+                                       const char *prefix)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t i;
+    size_t n = *size;
+    char *p = *buf;
+    const mbedtls_x509_sequence *cur = subject_alt_name;
+    mbedtls_x509_subject_alternative_name san;
+    int parse_ret;
+
+    while (cur != NULL) {
+        memset(&san, 0, sizeof(san));
+        parse_ret = mbedtls_x509_parse_subject_alt_name(&cur->buf, &san);
+        if (parse_ret != 0) {
+            if (parse_ret == MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE) {
+                ret = mbedtls_snprintf(p, n, "\n%s    <unsupported>", prefix);
+                MBEDTLS_X509_SAFE_SNPRINTF;
+            } else {
+                ret = mbedtls_snprintf(p, n, "\n%s    <malformed>", prefix);
+                MBEDTLS_X509_SAFE_SNPRINTF;
+            }
+            cur = cur->next;
+            continue;
+        }
+
+        switch (san.type) {
+            /*
+             * otherName
+             */
+            case MBEDTLS_X509_SAN_OTHER_NAME:
+            {
+                mbedtls_x509_san_other_name *other_name = &san.san.other_name;
+
+                ret = mbedtls_snprintf(p, n, "\n%s    otherName :", prefix);
+                MBEDTLS_X509_SAFE_SNPRINTF;
+
+                if (MBEDTLS_OID_CMP(MBEDTLS_OID_ON_HW_MODULE_NAME,
+                                    &other_name->value.hardware_module_name.oid) != 0) {
+                    ret = mbedtls_snprintf(p, n, "\n%s        hardware module name :", prefix);
+                    MBEDTLS_X509_SAFE_SNPRINTF;
+                    ret =
+                        mbedtls_snprintf(p, n, "\n%s            hardware type          : ", prefix);
+                    MBEDTLS_X509_SAFE_SNPRINTF;
+
+                    ret = mbedtls_oid_get_numeric_string(p,
+                                                         n,
+                                                         &other_name->value.hardware_module_name.oid);
+                    MBEDTLS_X509_SAFE_SNPRINTF;
+
+                    ret =
+                        mbedtls_snprintf(p, n, "\n%s            hardware serial number : ", prefix);
+                    MBEDTLS_X509_SAFE_SNPRINTF;
+
+                    for (i = 0; i < other_name->value.hardware_module_name.val.len; i++) {
+                        ret = mbedtls_snprintf(p,
+                                               n,
+                                               "%02X",
+                                               other_name->value.hardware_module_name.val.p[i]);
+                        MBEDTLS_X509_SAFE_SNPRINTF;
+                    }
+                }/* MBEDTLS_OID_ON_HW_MODULE_NAME */
+            }
+            break;
+
+            /*
+             * dNSName
+             */
+            case MBEDTLS_X509_SAN_DNS_NAME:
+            {
+                ret = mbedtls_snprintf(p, n, "\n%s    dNSName : ", prefix);
+                MBEDTLS_X509_SAFE_SNPRINTF;
+                if (san.san.unstructured_name.len >= n) {
+                    *p = '\0';
+                    return MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
+                }
+
+                memcpy(p, san.san.unstructured_name.p, san.san.unstructured_name.len);
+                p += san.san.unstructured_name.len;
+                n -= san.san.unstructured_name.len;
+            }
+            break;
+
+            /*
+             * Type not supported, skip item.
+             */
+            default:
+                ret = mbedtls_snprintf(p, n, "\n%s    <unsupported>", prefix);
+                MBEDTLS_X509_SAFE_SNPRINTF;
+                break;
+        }
+
+        cur = cur->next;
+    }
+
+    *p = '\0';
+
+    *size = n;
+    *buf = p;
+
+    return 0;
+}
+
+#define PRINT_ITEM(i)                           \
+    {                                           \
+        ret = mbedtls_snprintf(p, n, "%s" i, sep);    \
+        MBEDTLS_X509_SAFE_SNPRINTF;                        \
+        sep = ", ";                             \
+    }
+
+#define CERT_TYPE(type, name)                    \
+    if (ns_cert_type & (type))                 \
+    PRINT_ITEM(name);
+
+int mbedtls_x509_info_cert_type(char **buf, size_t *size,
+                                unsigned char ns_cert_type)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t n = *size;
+    char *p = *buf;
+    const char *sep = "";
+
+    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT,         "SSL Client");
+    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER,         "SSL Server");
+    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_EMAIL,              "Email");
+    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING,     "Object Signing");
+    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_RESERVED,           "Reserved");
+    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_SSL_CA,             "SSL CA");
+    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA,           "Email CA");
+    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA,  "Object Signing CA");
+
+    *size = n;
+    *buf = p;
+
+    return 0;
+}
+
+#define KEY_USAGE(code, name)    \
+    if (key_usage & (code))    \
+    PRINT_ITEM(name);
+
+int mbedtls_x509_info_key_usage(char **buf, size_t *size,
+                                unsigned int key_usage)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t n = *size;
+    char *p = *buf;
+    const char *sep = "";
+
+    KEY_USAGE(MBEDTLS_X509_KU_DIGITAL_SIGNATURE,    "Digital Signature");
+    KEY_USAGE(MBEDTLS_X509_KU_NON_REPUDIATION,      "Non Repudiation");
+    KEY_USAGE(MBEDTLS_X509_KU_KEY_ENCIPHERMENT,     "Key Encipherment");
+    KEY_USAGE(MBEDTLS_X509_KU_DATA_ENCIPHERMENT,    "Data Encipherment");
+    KEY_USAGE(MBEDTLS_X509_KU_KEY_AGREEMENT,        "Key Agreement");
+    KEY_USAGE(MBEDTLS_X509_KU_KEY_CERT_SIGN,        "Key Cert Sign");
+    KEY_USAGE(MBEDTLS_X509_KU_CRL_SIGN,             "CRL Sign");
+    KEY_USAGE(MBEDTLS_X509_KU_ENCIPHER_ONLY,        "Encipher Only");
+    KEY_USAGE(MBEDTLS_X509_KU_DECIPHER_ONLY,        "Decipher Only");
+
+    *size = n;
+    *buf = p;
+
+    return 0;
+}
+#endif /* MBEDTLS_X509_REMOVE_INFO */
+#endif /* MBEDTLS_X509_CRT_PARSE_C || MBEDTLS_X509_CSR_PARSE_C */
 #endif /* MBEDTLS_X509_USE_C */
diff --git a/library/x509_crt.c b/library/x509_crt.c
index eabafe9..ecb903f 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -562,53 +562,6 @@
     return 0;
 }
 
-static int x509_get_ns_cert_type(unsigned char **p,
-                                 const unsigned char *end,
-                                 unsigned char *ns_cert_type)
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    mbedtls_x509_bitstring bs = { 0, 0, NULL };
-
-    if ((ret = mbedtls_asn1_get_bitstring(p, end, &bs)) != 0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
-    }
-
-    if (bs.len != 1) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                 MBEDTLS_ERR_ASN1_INVALID_LENGTH);
-    }
-
-    /* Get actual bitstring */
-    *ns_cert_type = *bs.p;
-    return 0;
-}
-
-static int x509_get_key_usage(unsigned char **p,
-                              const unsigned char *end,
-                              unsigned int *key_usage)
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t i;
-    mbedtls_x509_bitstring bs = { 0, 0, NULL };
-
-    if ((ret = mbedtls_asn1_get_bitstring(p, end, &bs)) != 0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
-    }
-
-    if (bs.len < 1) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                 MBEDTLS_ERR_ASN1_INVALID_LENGTH);
-    }
-
-    /* Get actual bitstring */
-    *key_usage = 0;
-    for (i = 0; i < bs.len && i < sizeof(unsigned int); i++) {
-        *key_usage |= (unsigned int) bs.p[i] << (8*i);
-    }
-
-    return 0;
-}
-
 /*
  * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
  *
@@ -634,118 +587,6 @@
 }
 
 /*
- * SubjectAltName ::= GeneralNames
- *
- * GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
- *
- * GeneralName ::= CHOICE {
- *      otherName                       [0]     OtherName,
- *      rfc822Name                      [1]     IA5String,
- *      dNSName                         [2]     IA5String,
- *      x400Address                     [3]     ORAddress,
- *      directoryName                   [4]     Name,
- *      ediPartyName                    [5]     EDIPartyName,
- *      uniformResourceIdentifier       [6]     IA5String,
- *      iPAddress                       [7]     OCTET STRING,
- *      registeredID                    [8]     OBJECT IDENTIFIER }
- *
- * OtherName ::= SEQUENCE {
- *      type-id    OBJECT IDENTIFIER,
- *      value      [0] EXPLICIT ANY DEFINED BY type-id }
- *
- * EDIPartyName ::= SEQUENCE {
- *      nameAssigner            [0]     DirectoryString OPTIONAL,
- *      partyName               [1]     DirectoryString }
- *
- * NOTE: we list all types, but only use dNSName and otherName
- * of type HwModuleName, as defined in RFC 4108, at this point.
- */
-static int x509_get_subject_alt_name(unsigned char **p,
-                                     const unsigned char *end,
-                                     mbedtls_x509_sequence *subject_alt_name)
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t len, tag_len;
-    mbedtls_asn1_buf *buf;
-    unsigned char tag;
-    mbedtls_asn1_sequence *cur = subject_alt_name;
-
-    /* Get main sequence tag */
-    if ((ret = mbedtls_asn1_get_tag(p, end, &len,
-                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
-    }
-
-    if (*p + len != end) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
-    }
-
-    while (*p < end) {
-        mbedtls_x509_subject_alternative_name dummy_san_buf;
-        memset(&dummy_san_buf, 0, sizeof(dummy_san_buf));
-
-        tag = **p;
-        (*p)++;
-        if ((ret = mbedtls_asn1_get_len(p, end, &tag_len)) != 0) {
-            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
-        }
-
-        if ((tag & MBEDTLS_ASN1_TAG_CLASS_MASK) !=
-            MBEDTLS_ASN1_CONTEXT_SPECIFIC) {
-            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                     MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
-        }
-
-        /*
-         * Check that the SAN is structured correctly.
-         */
-        ret = mbedtls_x509_parse_subject_alt_name(&(cur->buf), &dummy_san_buf);
-        /*
-         * In case the extension is malformed, return an error,
-         * and clear the allocated sequences.
-         */
-        if (ret != 0 && ret != MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE) {
-            mbedtls_asn1_sequence_free(subject_alt_name->next);
-            subject_alt_name->next = NULL;
-            return ret;
-        }
-
-        /* Allocate and assign next pointer */
-        if (cur->buf.p != NULL) {
-            if (cur->next != NULL) {
-                return MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
-            }
-
-            cur->next = mbedtls_calloc(1, sizeof(mbedtls_asn1_sequence));
-
-            if (cur->next == NULL) {
-                return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                         MBEDTLS_ERR_ASN1_ALLOC_FAILED);
-            }
-
-            cur = cur->next;
-        }
-
-        buf = &(cur->buf);
-        buf->tag = tag;
-        buf->p = *p;
-        buf->len = tag_len;
-        *p += buf->len;
-    }
-
-    /* Set final sequence entry's next pointer to NULL */
-    cur->next = NULL;
-
-    if (*p != end) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
-    }
-
-    return 0;
-}
-
-/*
  * id-ce-certificatePolicies OBJECT IDENTIFIER ::=  { id-ce 32 }
  *
  * anyPolicy OBJECT IDENTIFIER ::= { id-ce-certificatePolicies 0 }
@@ -1029,8 +870,8 @@
 
             case MBEDTLS_X509_EXT_KEY_USAGE:
                 /* Parse key usage */
-                if ((ret = x509_get_key_usage(p, end_ext_octet,
-                                              &crt->key_usage)) != 0) {
+                if ((ret = mbedtls_x509_get_key_usage(p, end_ext_octet,
+                                                      &crt->key_usage)) != 0) {
                     return ret;
                 }
                 break;
@@ -1045,16 +886,16 @@
 
             case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
                 /* Parse subject alt name */
-                if ((ret = x509_get_subject_alt_name(p, end_ext_octet,
-                                                     &crt->subject_alt_names)) != 0) {
+                if ((ret = mbedtls_x509_get_subject_alt_name(p, end_ext_octet,
+                                                             &crt->subject_alt_names)) != 0) {
                     return ret;
                 }
                 break;
 
             case MBEDTLS_X509_EXT_NS_CERT_TYPE:
                 /* Parse netscape certificate type */
-                if ((ret = x509_get_ns_cert_type(p, end_ext_octet,
-                                                 &crt->ns_cert_type)) != 0) {
+                if ((ret = mbedtls_x509_get_ns_cert_type(p, end_ext_octet,
+                                                         &crt->ns_cert_type)) != 0) {
                     return ret;
                 }
                 break;
@@ -1703,319 +1544,7 @@
 }
 #endif /* MBEDTLS_FS_IO */
 
-/*
- * OtherName ::= SEQUENCE {
- *      type-id    OBJECT IDENTIFIER,
- *      value      [0] EXPLICIT ANY DEFINED BY type-id }
- *
- * HardwareModuleName ::= SEQUENCE {
- *                           hwType OBJECT IDENTIFIER,
- *                           hwSerialNum OCTET STRING }
- *
- * NOTE: we currently only parse and use otherName of type HwModuleName,
- * as defined in RFC 4108.
- */
-static int x509_get_other_name(const mbedtls_x509_buf *subject_alt_name,
-                               mbedtls_x509_san_other_name *other_name)
-{
-    int ret = 0;
-    size_t len;
-    unsigned char *p = subject_alt_name->p;
-    const unsigned char *end = p + subject_alt_name->len;
-    mbedtls_x509_buf cur_oid;
-
-    if ((subject_alt_name->tag &
-         (MBEDTLS_ASN1_TAG_CLASS_MASK | MBEDTLS_ASN1_TAG_VALUE_MASK)) !=
-        (MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_OTHER_NAME)) {
-        /*
-         * The given subject alternative name is not of type "othername".
-         */
-        return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
-    }
-
-    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
-                                    MBEDTLS_ASN1_OID)) != 0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
-    }
-
-    cur_oid.tag = MBEDTLS_ASN1_OID;
-    cur_oid.p = p;
-    cur_oid.len = len;
-
-    /*
-     * Only HwModuleName is currently supported.
-     */
-    if (MBEDTLS_OID_CMP(MBEDTLS_OID_ON_HW_MODULE_NAME, &cur_oid) != 0) {
-        return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
-    }
-
-    if (p + len >= end) {
-        mbedtls_platform_zeroize(other_name, sizeof(*other_name));
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
-    }
-    p += len;
-    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
-                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_CONTEXT_SPECIFIC)) !=
-        0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
-    }
-
-    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
-                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
-    }
-
-    if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OID)) != 0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
-    }
-
-    other_name->value.hardware_module_name.oid.tag = MBEDTLS_ASN1_OID;
-    other_name->value.hardware_module_name.oid.p = p;
-    other_name->value.hardware_module_name.oid.len = len;
-
-    if (p + len >= end) {
-        mbedtls_platform_zeroize(other_name, sizeof(*other_name));
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
-    }
-    p += len;
-    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
-                                    MBEDTLS_ASN1_OCTET_STRING)) != 0) {
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
-    }
-
-    other_name->value.hardware_module_name.val.tag = MBEDTLS_ASN1_OCTET_STRING;
-    other_name->value.hardware_module_name.val.p = p;
-    other_name->value.hardware_module_name.val.len = len;
-    p += len;
-    if (p != end) {
-        mbedtls_platform_zeroize(other_name,
-                                 sizeof(*other_name));
-        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
-    }
-    return 0;
-}
-
-int mbedtls_x509_parse_subject_alt_name(const mbedtls_x509_buf *san_buf,
-                                        mbedtls_x509_subject_alternative_name *san)
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    switch (san_buf->tag &
-            (MBEDTLS_ASN1_TAG_CLASS_MASK |
-             MBEDTLS_ASN1_TAG_VALUE_MASK)) {
-        /*
-         * otherName
-         */
-        case (MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_OTHER_NAME):
-        {
-            mbedtls_x509_san_other_name other_name;
-
-            ret = x509_get_other_name(san_buf, &other_name);
-            if (ret != 0) {
-                return ret;
-            }
-
-            memset(san, 0, sizeof(mbedtls_x509_subject_alternative_name));
-            san->type = MBEDTLS_X509_SAN_OTHER_NAME;
-            memcpy(&san->san.other_name,
-                   &other_name, sizeof(other_name));
-
-        }
-        break;
-
-        /*
-         * dNSName
-         */
-        case (MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_DNS_NAME):
-        {
-            memset(san, 0, sizeof(mbedtls_x509_subject_alternative_name));
-            san->type = MBEDTLS_X509_SAN_DNS_NAME;
-
-            memcpy(&san->san.unstructured_name,
-                   san_buf, sizeof(*san_buf));
-
-        }
-        break;
-
-        /*
-         * Type not supported
-         */
-        default:
-            return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
-    }
-    return 0;
-}
-
 #if !defined(MBEDTLS_X509_REMOVE_INFO)
-static int x509_info_subject_alt_name(char **buf, size_t *size,
-                                      const mbedtls_x509_sequence
-                                      *subject_alt_name,
-                                      const char *prefix)
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t i;
-    size_t n = *size;
-    char *p = *buf;
-    const mbedtls_x509_sequence *cur = subject_alt_name;
-    mbedtls_x509_subject_alternative_name san;
-    int parse_ret;
-
-    while (cur != NULL) {
-        memset(&san, 0, sizeof(san));
-        parse_ret = mbedtls_x509_parse_subject_alt_name(&cur->buf, &san);
-        if (parse_ret != 0) {
-            if (parse_ret == MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE) {
-                ret = mbedtls_snprintf(p, n, "\n%s    <unsupported>", prefix);
-                MBEDTLS_X509_SAFE_SNPRINTF;
-            } else {
-                ret = mbedtls_snprintf(p, n, "\n%s    <malformed>", prefix);
-                MBEDTLS_X509_SAFE_SNPRINTF;
-            }
-            cur = cur->next;
-            continue;
-        }
-
-        switch (san.type) {
-            /*
-             * otherName
-             */
-            case MBEDTLS_X509_SAN_OTHER_NAME:
-            {
-                mbedtls_x509_san_other_name *other_name = &san.san.other_name;
-
-                ret = mbedtls_snprintf(p, n, "\n%s    otherName :", prefix);
-                MBEDTLS_X509_SAFE_SNPRINTF;
-
-                if (MBEDTLS_OID_CMP(MBEDTLS_OID_ON_HW_MODULE_NAME,
-                                    &other_name->value.hardware_module_name.oid) != 0) {
-                    ret = mbedtls_snprintf(p, n, "\n%s        hardware module name :", prefix);
-                    MBEDTLS_X509_SAFE_SNPRINTF;
-                    ret =
-                        mbedtls_snprintf(p, n, "\n%s            hardware type          : ", prefix);
-                    MBEDTLS_X509_SAFE_SNPRINTF;
-
-                    ret = mbedtls_oid_get_numeric_string(p,
-                                                         n,
-                                                         &other_name->value.hardware_module_name.oid);
-                    MBEDTLS_X509_SAFE_SNPRINTF;
-
-                    ret =
-                        mbedtls_snprintf(p, n, "\n%s            hardware serial number : ", prefix);
-                    MBEDTLS_X509_SAFE_SNPRINTF;
-
-                    for (i = 0; i < other_name->value.hardware_module_name.val.len; i++) {
-                        ret = mbedtls_snprintf(p,
-                                               n,
-                                               "%02X",
-                                               other_name->value.hardware_module_name.val.p[i]);
-                        MBEDTLS_X509_SAFE_SNPRINTF;
-                    }
-                }/* MBEDTLS_OID_ON_HW_MODULE_NAME */
-            }
-            break;
-
-            /*
-             * dNSName
-             */
-            case MBEDTLS_X509_SAN_DNS_NAME:
-            {
-                ret = mbedtls_snprintf(p, n, "\n%s    dNSName : ", prefix);
-                MBEDTLS_X509_SAFE_SNPRINTF;
-                if (san.san.unstructured_name.len >= n) {
-                    *p = '\0';
-                    return MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
-                }
-
-                memcpy(p, san.san.unstructured_name.p, san.san.unstructured_name.len);
-                p += san.san.unstructured_name.len;
-                n -= san.san.unstructured_name.len;
-            }
-            break;
-
-            /*
-             * Type not supported, skip item.
-             */
-            default:
-                ret = mbedtls_snprintf(p, n, "\n%s    <unsupported>", prefix);
-                MBEDTLS_X509_SAFE_SNPRINTF;
-                break;
-        }
-
-        cur = cur->next;
-    }
-
-    *p = '\0';
-
-    *size = n;
-    *buf = p;
-
-    return 0;
-}
-
-#define PRINT_ITEM(i)                           \
-    {                                           \
-        ret = mbedtls_snprintf(p, n, "%s" i, sep);    \
-        MBEDTLS_X509_SAFE_SNPRINTF;                        \
-        sep = ", ";                             \
-    }
-
-#define CERT_TYPE(type, name)                    \
-    if (ns_cert_type & (type))                 \
-    PRINT_ITEM(name);
-
-static int x509_info_cert_type(char **buf, size_t *size,
-                               unsigned char ns_cert_type)
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t n = *size;
-    char *p = *buf;
-    const char *sep = "";
-
-    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT,         "SSL Client");
-    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER,         "SSL Server");
-    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_EMAIL,              "Email");
-    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING,     "Object Signing");
-    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_RESERVED,           "Reserved");
-    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_SSL_CA,             "SSL CA");
-    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA,           "Email CA");
-    CERT_TYPE(MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA,  "Object Signing CA");
-
-    *size = n;
-    *buf = p;
-
-    return 0;
-}
-
-#define KEY_USAGE(code, name)    \
-    if (key_usage & (code))    \
-    PRINT_ITEM(name);
-
-static int x509_info_key_usage(char **buf, size_t *size,
-                               unsigned int key_usage)
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t n = *size;
-    char *p = *buf;
-    const char *sep = "";
-
-    KEY_USAGE(MBEDTLS_X509_KU_DIGITAL_SIGNATURE,    "Digital Signature");
-    KEY_USAGE(MBEDTLS_X509_KU_NON_REPUDIATION,      "Non Repudiation");
-    KEY_USAGE(MBEDTLS_X509_KU_KEY_ENCIPHERMENT,     "Key Encipherment");
-    KEY_USAGE(MBEDTLS_X509_KU_DATA_ENCIPHERMENT,    "Data Encipherment");
-    KEY_USAGE(MBEDTLS_X509_KU_KEY_AGREEMENT,        "Key Agreement");
-    KEY_USAGE(MBEDTLS_X509_KU_KEY_CERT_SIGN,        "Key Cert Sign");
-    KEY_USAGE(MBEDTLS_X509_KU_CRL_SIGN,             "CRL Sign");
-    KEY_USAGE(MBEDTLS_X509_KU_ENCIPHER_ONLY,        "Encipher Only");
-    KEY_USAGE(MBEDTLS_X509_KU_DECIPHER_ONLY,        "Decipher Only");
-
-    *size = n;
-    *buf = p;
-
-    return 0;
-}
-
 static int x509_info_ext_key_usage(char **buf, size_t *size,
                                    const mbedtls_x509_sequence *extended_key_usage)
 {
@@ -2167,9 +1696,9 @@
         ret = mbedtls_snprintf(p, n, "\n%ssubject alt name  :", prefix);
         MBEDTLS_X509_SAFE_SNPRINTF;
 
-        if ((ret = x509_info_subject_alt_name(&p, &n,
-                                              &crt->subject_alt_names,
-                                              prefix)) != 0) {
+        if ((ret = mbedtls_x509_info_subject_alt_name(&p, &n,
+                                                      &crt->subject_alt_names,
+                                                      prefix)) != 0) {
             return ret;
         }
     }
@@ -2178,7 +1707,7 @@
         ret = mbedtls_snprintf(p, n, "\n%scert. type        : ", prefix);
         MBEDTLS_X509_SAFE_SNPRINTF;
 
-        if ((ret = x509_info_cert_type(&p, &n, crt->ns_cert_type)) != 0) {
+        if ((ret = mbedtls_x509_info_cert_type(&p, &n, crt->ns_cert_type)) != 0) {
             return ret;
         }
     }
@@ -2187,7 +1716,7 @@
         ret = mbedtls_snprintf(p, n, "\n%skey usage         : ", prefix);
         MBEDTLS_X509_SAFE_SNPRINTF;
 
-        if ((ret = x509_info_key_usage(&p, &n, crt->key_usage)) != 0) {
+        if ((ret = mbedtls_x509_info_key_usage(&p, &n, crt->key_usage)) != 0) {
             return ret;
         }
     }
diff --git a/library/x509_csr.c b/library/x509_csr.c
index 0c664d9..cd117cb 100644
--- a/library/x509_csr.c
+++ b/library/x509_csr.c
@@ -70,6 +70,165 @@
 }
 
 /*
+ * Parse CSR extension requests in DER format
+ */
+static int x509_csr_parse_extensions(mbedtls_x509_csr *csr,
+                                     unsigned char **p, const unsigned char *end)
+{
+    int ret;
+    size_t len;
+    unsigned char *end_ext_data;
+    while (*p < end) {
+        mbedtls_x509_buf extn_oid = { 0, 0, NULL };
+        int ext_type = 0;
+
+        /* Read sequence tag */
+        if ((ret = mbedtls_asn1_get_tag(p, end, &len,
+                                        MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+        }
+
+        end_ext_data = *p + len;
+
+        /* Get extension ID */
+        if ((ret = mbedtls_asn1_get_tag(p, end_ext_data, &extn_oid.len,
+                                        MBEDTLS_ASN1_OID)) != 0) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+        }
+
+        extn_oid.tag = MBEDTLS_ASN1_OID;
+        extn_oid.p = *p;
+        *p += extn_oid.len;
+
+        /* Data should be octet string type */
+        if ((ret = mbedtls_asn1_get_tag(p, end_ext_data, &len,
+                                        MBEDTLS_ASN1_OCTET_STRING)) != 0) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+        }
+
+        if (*p + len != end_ext_data) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+        }
+
+        /*
+         * Detect supported extensions and skip unsupported extensions
+         */
+        ret = mbedtls_oid_get_x509_ext_type(&extn_oid, &ext_type);
+
+        if (ret == 0) {
+            /* Forbid repeated extensions */
+            if ((csr->ext_types & ext_type) != 0) {
+                return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                         MBEDTLS_ERR_ASN1_INVALID_DATA);
+            }
+
+            csr->ext_types |= ext_type;
+
+            switch (ext_type) {
+                case MBEDTLS_X509_EXT_KEY_USAGE:
+                    /* Parse key usage */
+                    if ((ret = mbedtls_x509_get_key_usage(p, end_ext_data,
+                                                          &csr->key_usage)) != 0) {
+                        return ret;
+                    }
+                    break;
+
+                case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
+                    /* Parse subject alt name */
+                    if ((ret = mbedtls_x509_get_subject_alt_name(p, end_ext_data,
+                                                                 &csr->subject_alt_names)) != 0) {
+                        return ret;
+                    }
+                    break;
+
+                case MBEDTLS_X509_EXT_NS_CERT_TYPE:
+                    /* Parse netscape certificate type */
+                    if ((ret = mbedtls_x509_get_ns_cert_type(p, end_ext_data,
+                                                             &csr->ns_cert_type)) != 0) {
+                        return ret;
+                    }
+                    break;
+                default:
+                    break;
+            }
+        }
+        *p = end_ext_data;
+    }
+
+    if (*p != end) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    return 0;
+}
+
+/*
+ * Parse CSR attributes in DER format
+ */
+static int x509_csr_parse_attributes(mbedtls_x509_csr *csr,
+                                     const unsigned char *start, const unsigned char *end)
+{
+    int ret;
+    size_t len;
+    unsigned char *end_attr_data;
+    unsigned char **p = (unsigned char **) &start;
+
+    while (*p < end) {
+        mbedtls_x509_buf attr_oid = { 0, 0, NULL };
+
+        if ((ret = mbedtls_asn1_get_tag(p, end, &len,
+                                        MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+        }
+        end_attr_data = *p + len;
+
+        /* Get attribute ID */
+        if ((ret = mbedtls_asn1_get_tag(p, end_attr_data, &attr_oid.len,
+                                        MBEDTLS_ASN1_OID)) != 0) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+        }
+
+        attr_oid.tag = MBEDTLS_ASN1_OID;
+        attr_oid.p = *p;
+        *p += attr_oid.len;
+
+        /* Check that this is an extension-request attribute */
+        if (MBEDTLS_OID_CMP(MBEDTLS_OID_PKCS9_CSR_EXT_REQ, &attr_oid) == 0) {
+            if ((ret = mbedtls_asn1_get_tag(p, end, &len,
+                                            MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SET)) != 0) {
+                return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+            }
+
+            if ((ret = mbedtls_asn1_get_tag(p, end, &len,
+                                            MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) !=
+                0) {
+                return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+            }
+
+            if ((ret = x509_csr_parse_extensions(csr, p, *p + len)) != 0) {
+                return ret;
+            }
+
+            if (*p != end_attr_data) {
+                return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                         MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+            }
+        }
+
+        *p = end_attr_data;
+    }
+
+    if (*p != end) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    return 0;
+}
+
+/*
  * Parse a CSR in DER format
  */
 int mbedtls_x509_csr_parse_der(mbedtls_x509_csr *csr,
@@ -197,6 +356,11 @@
         return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
     }
 
+    if ((ret = x509_csr_parse_attributes(csr, p, p + len)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return ret;
+    }
+
     p += len;
 
     end = csr->raw.p + csr->raw.len;
@@ -345,6 +509,44 @@
                            (int) mbedtls_pk_get_bitlen(&csr->pk));
     MBEDTLS_X509_SAFE_SNPRINTF;
 
+    /*
+     * Optional extensions
+     */
+
+    if (csr->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME) {
+        ret = mbedtls_snprintf(p, n, "\n%ssubject alt name  :", prefix);
+        MBEDTLS_X509_SAFE_SNPRINTF;
+
+        if ((ret = mbedtls_x509_info_subject_alt_name(&p, &n,
+                                                      &csr->subject_alt_names,
+                                                      prefix)) != 0) {
+            return ret;
+        }
+    }
+
+    if (csr->ext_types & MBEDTLS_X509_EXT_NS_CERT_TYPE) {
+        ret = mbedtls_snprintf(p, n, "\n%scert. type        : ", prefix);
+        MBEDTLS_X509_SAFE_SNPRINTF;
+
+        if ((ret = mbedtls_x509_info_cert_type(&p, &n, csr->ns_cert_type)) != 0) {
+            return ret;
+        }
+    }
+
+    if (csr->ext_types & MBEDTLS_X509_EXT_KEY_USAGE) {
+        ret = mbedtls_snprintf(p, n, "\n%skey usage         : ", prefix);
+        MBEDTLS_X509_SAFE_SNPRINTF;
+
+        if ((ret = mbedtls_x509_info_key_usage(&p, &n, csr->key_usage)) != 0) {
+            return ret;
+        }
+    }
+
+    if (csr->ext_types != 0) {
+        ret = mbedtls_snprintf(p, n, "\n");
+        MBEDTLS_X509_SAFE_SNPRINTF;
+    }
+
     return (int) (size - n);
 }
 #endif /* MBEDTLS_X509_REMOVE_INFO */
@@ -373,6 +575,7 @@
 #endif
 
     mbedtls_asn1_free_named_data_list_shallow(csr->subject.next);
+    mbedtls_asn1_sequence_free(csr->subject_alt_names.next);
 
     if (csr->raw.p != NULL) {
         mbedtls_platform_zeroize(csr->raw.p, csr->raw.len);
diff --git a/tests/data_files/Makefile b/tests/data_files/Makefile
index 9c7a95d..cf25426 100644
--- a/tests/data_files/Makefile
+++ b/tests/data_files/Makefile
@@ -93,6 +93,53 @@
 cert_example_multi.crt: cert_example_multi.csr
 	$(OPENSSL) x509 -req -CA $(test_ca_crt) -CAkey $(test_ca_key_file_rsa) -extfile $(test_ca_config_file) -extensions dns_alt_names -passin "pass:$(test_ca_pwd_rsa)" -set_serial 17 -days 3653 -sha256 -in $< > $@
 
+test_csr_v3_keyUsage.csr.der: rsa_pkcs1_1024_clear.pem
+	$(OPENSSL) req -new -subj '/CN=etcd' -config $(test_ca_config_file) -key rsa_pkcs1_1024_clear.pem -outform DER -out $@ -reqexts csr_ext_v3_keyUsage
+test_csr_v3_subjectAltName.csr.der: rsa_pkcs1_1024_clear.pem
+	$(OPENSSL) req -new -subj '/CN=etcd' -config $(test_ca_config_file) -key rsa_pkcs1_1024_clear.pem -outform DER -out $@ -reqexts csr_ext_v3_subjectAltName
+test_csr_v3_nsCertType.csr.der: rsa_pkcs1_1024_clear.pem
+	$(OPENSSL) req -new -subj '/CN=etcd' -config $(test_ca_config_file) -key rsa_pkcs1_1024_clear.pem -outform DER -out $@ -reqexts csr_ext_v3_nsCertType
+test_csr_v3_all.csr.der: rsa_pkcs1_1024_clear.pem
+	$(OPENSSL) req -new -subj '/CN=etcd' -config $(test_ca_config_file) -key rsa_pkcs1_1024_clear.pem -outform DER -out $@ -reqexts csr_ext_v3_all
+test_csr_v3_all_malformed_extensions_sequence_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/300B0603551D0F040403/200B0603551D0F040403/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_extension_id_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/0603551D0F0404030201/0703551D0F0404030201/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_extension_data_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/040403020102302F0603/050403020102302F0603/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_extension_data_len1.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/040403020102302F0603/040503020102302F0603/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_extension_data_len2.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/040403020102302F0603/040303020102302F0603/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_extension_key_usage_bitstream_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/03020102302F0603551D/04020102302F0603551D/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_extension_subject_alt_name_sequence_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/3026A02406082B060105/4026A02406082B060105/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_extension_ns_cert_bitstream_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/03020780300D06092A86/04020780300D06092A86/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_duplicated_extension.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/551D11/551D0F/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_extension_type_oid.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/551D11/551DFF/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_attributes_sequence_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/306006092A864886F70D/406006092A864886F70D/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_attributes_id_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/06092A864886F70D0109/07092A864886F70D0109/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_attributes_extension_request.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/2A864886F70D01090E/2A864886F70D01090F/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_attributes_extension_request_set_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/31533051300B0603551D/32533051300B0603551D/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_attributes_extension_request_sequence_tag.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/3051300B0603551D0F04/3151300B0603551D0F04/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_attributes_len1.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/306006092A864886F70D/306106092A864886F70D/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_attributes_len2.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/306006092A864886F70D/305906092A864886F70D/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_attributes_extension_request_sequence_len1.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/3051300B0603551D0F04/3052300B0603551D0F04/" | xxd -r -p ) > $@
+test_csr_v3_all_malformed_attributes_extension_request_sequence_len2.csr.der: test_csr_v3_all.csr.der
+	(hexdump -ve '1/1 "%.2X"' $< | sed "s/3051300B0603551D0F04/3050300B0603551D0F04/" | xxd -r -p ) > $@
+
 $(test_ca_key_file_rsa_alt):test-ca.opensslconf
 	$(OPENSSL) genrsa -out $@ 2048
 test-ca-alt.csr: $(test_ca_key_file_rsa_alt) $(test_ca_config_file)
diff --git a/tests/data_files/test-ca.opensslconf b/tests/data_files/test-ca.opensslconf
index b2c2fa1..bd12760 100644
--- a/tests/data_files/test-ca.opensslconf
+++ b/tests/data_files/test-ca.opensslconf
@@ -82,3 +82,17 @@
 # these IPs are the ascii values for 'abcd' and 'abcd.example.com'
 [tricky_ip_san]
 subjectAltName=IP:97.98.99.100,IP:6162:6364:2e65:7861:6d70:6c65:2e63:6f6d
+
+[csr_ext_v3_keyUsage]
+keyUsage = digitalSignature, keyEncipherment
+
+[csr_ext_v3_subjectAltName]
+subjectAltName=DNS:example.com, DNS:example.net, DNS:*.example.org
+
+[csr_ext_v3_nsCertType]
+nsCertType=server
+
+[csr_ext_v3_all]
+keyUsage = cRLSign
+subjectAltName=otherName:1.3.6.1.5.5.7.8.4;SEQ:nonprintable_hw_module_name
+nsCertType=client
diff --git a/tests/data_files/test_csr_v3_all.csr.der b/tests/data_files/test_csr_v3_all.csr.der
new file mode 100644
index 0000000..7e717f3
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request.csr.der b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request.csr.der
new file mode 100644
index 0000000..96a11e8
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_len1.csr.der b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_len1.csr.der
new file mode 100644
index 0000000..f61c7c8
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_len1.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_len2.csr.der b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_len2.csr.der
new file mode 100644
index 0000000..e6db2cc
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_len2.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_tag.csr.der
new file mode 100644
index 0000000..620fa7d
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_set_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_set_tag.csr.der
new file mode 100644
index 0000000..1d358e5
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_attributes_extension_request_set_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_attributes_id_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_attributes_id_tag.csr.der
new file mode 100644
index 0000000..f8d0689
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_attributes_id_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_attributes_len1.csr.der b/tests/data_files/test_csr_v3_all_malformed_attributes_len1.csr.der
new file mode 100644
index 0000000..01eabff
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_attributes_len1.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_attributes_len2.csr.der b/tests/data_files/test_csr_v3_all_malformed_attributes_len2.csr.der
new file mode 100644
index 0000000..875db76
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_attributes_len2.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_attributes_sequence_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_attributes_sequence_tag.csr.der
new file mode 100644
index 0000000..38273ca
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_attributes_sequence_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_duplicated_extension.csr.der b/tests/data_files/test_csr_v3_all_malformed_duplicated_extension.csr.der
new file mode 100644
index 0000000..4e2a221
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_duplicated_extension.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_extension_data_len1.csr.der b/tests/data_files/test_csr_v3_all_malformed_extension_data_len1.csr.der
new file mode 100644
index 0000000..6116118
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_extension_data_len1.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_extension_data_len2.csr.der b/tests/data_files/test_csr_v3_all_malformed_extension_data_len2.csr.der
new file mode 100644
index 0000000..a49209a
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_extension_data_len2.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_extension_data_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_extension_data_tag.csr.der
new file mode 100644
index 0000000..ccae723
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_extension_data_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_extension_id_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_extension_id_tag.csr.der
new file mode 100644
index 0000000..989e404
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_extension_id_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_extension_key_usage_bitstream_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_extension_key_usage_bitstream_tag.csr.der
new file mode 100644
index 0000000..a6fd2d7
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_extension_key_usage_bitstream_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_extension_ns_cert_bitstream_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_extension_ns_cert_bitstream_tag.csr.der
new file mode 100644
index 0000000..6fdcfc8
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_extension_ns_cert_bitstream_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_extension_subject_alt_name_sequence_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_extension_subject_alt_name_sequence_tag.csr.der
new file mode 100644
index 0000000..f1090f9
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_extension_subject_alt_name_sequence_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_extension_type_oid.csr.der b/tests/data_files/test_csr_v3_all_malformed_extension_type_oid.csr.der
new file mode 100644
index 0000000..36bc61e
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_extension_type_oid.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_all_malformed_extensions_sequence_tag.csr.der b/tests/data_files/test_csr_v3_all_malformed_extensions_sequence_tag.csr.der
new file mode 100644
index 0000000..fecb15e
--- /dev/null
+++ b/tests/data_files/test_csr_v3_all_malformed_extensions_sequence_tag.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_keyUsage.csr.der b/tests/data_files/test_csr_v3_keyUsage.csr.der
new file mode 100644
index 0000000..f8be020
--- /dev/null
+++ b/tests/data_files/test_csr_v3_keyUsage.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_nsCertType.csr.der b/tests/data_files/test_csr_v3_nsCertType.csr.der
new file mode 100644
index 0000000..cf9588d
--- /dev/null
+++ b/tests/data_files/test_csr_v3_nsCertType.csr.der
Binary files differ
diff --git a/tests/data_files/test_csr_v3_subjectAltName.csr.der b/tests/data_files/test_csr_v3_subjectAltName.csr.der
new file mode 100644
index 0000000..2ccb3bb
--- /dev/null
+++ b/tests/data_files/test_csr_v3_subjectAltName.csr.der
Binary files differ
diff --git a/tests/suites/test_suite_x509parse.data b/tests/suites/test_suite_x509parse.data
index 002f3dc..6821fe1 100644
--- a/tests/suites/test_suite_x509parse.data
+++ b/tests/suites/test_suite_x509parse.data
@@ -308,48 +308,64 @@
 
 X509 CSR Information EC with SHA1
 depends_on:MBEDTLS_ECDSA_C:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_HAS_ALG_SHA_1_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server5.req.sha1":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA1\nEC key size   \: 256 bits\n"
+mbedtls_x509_csr_info:"data_files/server5.req.sha1":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA1\nEC key size   \: 256 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information EC with SHA224
 depends_on:MBEDTLS_ECDSA_C:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_HAS_ALG_SHA_224_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server5.req.sha224":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA224\nEC key size   \: 256 bits\n"
+mbedtls_x509_csr_info:"data_files/server5.req.sha224":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA224\nEC key size   \: 256 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information EC with SHA256
 depends_on:MBEDTLS_ECDSA_C:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server5.req.sha256":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA256\nEC key size   \: 256 bits\n"
+mbedtls_x509_csr_info:"data_files/server5.req.sha256":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA256\nEC key size   \: 256 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information EC with SHA384
 depends_on:MBEDTLS_ECDSA_C:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_HAS_ALG_SHA_384_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server5.req.sha384":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA384\nEC key size   \: 256 bits\n"
+mbedtls_x509_csr_info:"data_files/server5.req.sha384":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA384\nEC key size   \: 256 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information EC with SHA512
 depends_on:MBEDTLS_ECDSA_C:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_HAS_ALG_SHA_512_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server5.req.sha512":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA512\nEC key size   \: 256 bits\n"
+mbedtls_x509_csr_info:"data_files/server5.req.sha512":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA512\nEC key size   \: 256 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information RSA-PSS with SHA1
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_X509_RSASSA_PSS_SUPPORT:MBEDTLS_HAS_ALG_SHA_1_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server9.req.sha1":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA1, MGF1-SHA1, 0x6A)\nRSA key size  \: 1024 bits\n"
+mbedtls_x509_csr_info:"data_files/server9.req.sha1":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA1, MGF1-SHA1, 0x6A)\nRSA key size  \: 1024 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information RSA-PSS with SHA224
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_X509_RSASSA_PSS_SUPPORT:MBEDTLS_HAS_ALG_SHA_224_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server9.req.sha224":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA224, MGF1-SHA224, 0x62)\nRSA key size  \: 1024 bits\n"
+mbedtls_x509_csr_info:"data_files/server9.req.sha224":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA224, MGF1-SHA224, 0x62)\nRSA key size  \: 1024 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information RSA-PSS with SHA256
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_X509_RSASSA_PSS_SUPPORT:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server9.req.sha256":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA256, MGF1-SHA256, 0x5E)\nRSA key size  \: 1024 bits\n"
+mbedtls_x509_csr_info:"data_files/server9.req.sha256":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA256, MGF1-SHA256, 0x5E)\nRSA key size  \: 1024 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information RSA-PSS with SHA384
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_X509_RSASSA_PSS_SUPPORT:MBEDTLS_HAS_ALG_SHA_384_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server9.req.sha384":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA384, MGF1-SHA384, 0x4E)\nRSA key size  \: 1024 bits\n"
+mbedtls_x509_csr_info:"data_files/server9.req.sha384":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA384, MGF1-SHA384, 0x4E)\nRSA key size  \: 1024 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information RSA-PSS with SHA512
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_X509_RSASSA_PSS_SUPPORT:MBEDTLS_HAS_ALG_SHA_512_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_info:"data_files/server9.req.sha512":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA512, MGF1-SHA512, 0x3E)\nRSA key size  \: 1024 bits\n"
+mbedtls_x509_csr_info:"data_files/server9.req.sha512":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: RSASSA-PSS (SHA512, MGF1-SHA512, 0x3E)\nRSA key size  \: 1024 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n"
 
 X509 CSR Information RSA with SHA-256 - Microsoft header
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
 mbedtls_x509_csr_info:"data_files/server1-ms.req.sha256":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=PolarSSL Server 1\nsigned using  \: RSA with SHA-256\nRSA key size  \: 2048 bits\n"
 
+X509 CSR Information v3 extensions #1 (all)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C:!MBEDTLS_X509_REMOVE_INFO
+mbedtls_x509_csr_info:"data_files/test_csr_v3_all.csr.der":"CSR version   \: 1\nsubject name  \: CN=etcd\nsigned using  \: RSA with SHA-256\nRSA key size  \: 1024 bits\n\nsubject alt name  \:\n    otherName \:\n        hardware module name \:\n            hardware type          \: 1.3.6.1.4.1.17.3\n            hardware serial number \: 3132338081008180333231\ncert. type        \: SSL Client\nkey usage         \: CRL Sign\n"
+
+X509 CSR Information v3 extensions #2 (nsCertType only)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C:!MBEDTLS_X509_REMOVE_INFO
+mbedtls_x509_csr_info:"data_files/test_csr_v3_nsCertType.csr.der":"CSR version   \: 1\nsubject name  \: CN=etcd\nsigned using  \: RSA with SHA-256\nRSA key size  \: 1024 bits\n\ncert. type        \: SSL Server\n"
+
+X509 CSR Information v3 extensions #3 (subjectAltName only)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C:!MBEDTLS_X509_REMOVE_INFO
+mbedtls_x509_csr_info:"data_files/test_csr_v3_subjectAltName.csr.der":"CSR version   \: 1\nsubject name  \: CN=etcd\nsigned using  \: RSA with SHA-256\nRSA key size  \: 1024 bits\n\nsubject alt name  \:\n    dNSName \: example.com\n    dNSName \: example.net\n    dNSName \: *.example.org\n"
+
+X509 CSR Information v3 extensions #4 (keyUsage only)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C:!MBEDTLS_X509_REMOVE_INFO
+mbedtls_x509_csr_info:"data_files/test_csr_v3_keyUsage.csr.der":"CSR version   \: 1\nsubject name  \: CN=etcd\nsigned using  \: RSA with SHA-256\nRSA key size  \: 1024 bits\n\nkey usage         \: Digital Signature, Key Encipherment\n"
+
 X509 Verify Information: empty
 x509_verify_info:0:"":""
 
@@ -2573,7 +2589,7 @@
 
 X509 CSR ASN.1 (OK)
 depends_on:MBEDTLS_ECDSA_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_HAS_ALG_SHA_1_VIA_MD_OR_PSA_BASED_ON_USE_PSA:!MBEDTLS_X509_REMOVE_INFO
-mbedtls_x509_csr_parse:"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":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA1\nEC key size   \: 256 bits\n":0
+mbedtls_x509_csr_parse:"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":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA1\nEC key size   \: 256 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n":0
 
 X509 CSR ASN.1 (bad first tag)
 mbedtls_x509_csr_parse:"3100":"":MBEDTLS_ERR_X509_INVALID_FORMAT
@@ -2664,6 +2680,84 @@
 X509 CSR ASN.1 (invalid version overflow)
 mbedtls_x509_csr_parse:"3008300602047fffffff":"":MBEDTLS_ERR_X509_UNKNOWN_VERSION
 
+# Used test_csr_v3_all.csr.der as a base for malforming CSR extenstions/attributes
+# Please see makefile for data_files to check malformation details (test_csr_v3_all_malformed_xxx.csr files)
+X509 CSR ASN.1 (attributes: invalid sequence tag)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_attributes_sequence_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (attributes: invalid attribute id)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_attributes_id_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (attributes: not extension request)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_attributes_extension_request.csr.der":"CSR version   \: 1\nsubject name  \: CN=etcd\nsigned using  \: RSA with SHA-256\nRSA key size  \: 1024 bits\n":0
+
+X509 CSR ASN.1 (attributes: invalid extenstion request set tag)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_attributes_extension_request_set_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (attributes: invalid extenstion request sequence tag)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (attributes: invalid len (len > data))
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_attributes_len1.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_OUT_OF_DATA
+
+X509 CSR ASN.1 (attributes: invalid len (len < data))
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_attributes_len2.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_LENGTH_MISMATCH
+
+X509 CSR ASN.1 (attributes: extension request invalid len (len > data))
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_len1.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_OUT_OF_DATA
+
+X509 CSR ASN.1 (attributes: extension request invalid len (len < data))
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_attributes_extension_request_sequence_len2.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_OUT_OF_DATA
+
+X509 CSR ASN.1 (extensions: invalid sequence tag)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_extensions_sequence_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (extensions: invalid extension id tag)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_extension_id_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (extensions: invalid extension data tag)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_extension_data_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (extensions: invalid extension data len (len > data))
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_extension_data_len1.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_OUT_OF_DATA
+
+X509 CSR ASN.1 (extensions: invalid extension data len (len < data))
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_extension_data_len2.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_LENGTH_MISMATCH
+
+X509 CSR ASN.1 (extensions: invalid extension key usage bitstream tag)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_extension_key_usage_bitstream_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (extensions: invalid extension subject alt name sequence tag)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_extension_subject_alt_name_sequence_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (extensions: invalid extension ns cert bitstream tag)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_extension_ns_cert_bitstream_tag.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (extensions: duplicated extension)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_duplicated_extension.csr.der":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_INVALID_DATA
+
+X509 CSR ASN.1 (extensions: invalid extension type data)
+depends_on:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
+mbedtls_x509_csr_parse_file:"data_files/test_csr_v3_all_malformed_extension_type_oid.csr.der":"CSR version   \: 1\nsubject name  \: CN=etcd\nsigned using  \: RSA with SHA-256\nRSA key size  \: 1024 bits\n\ncert. type        \: SSL Client\nkey usage         \: CRL Sign\n":0
+
 X509 File parse (no issues)
 depends_on:MBEDTLS_ECDSA_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA:MBEDTLS_RSA_C
 x509parse_crt_file:"data_files/server7_int-ca.crt":0
diff --git a/tests/suites/test_suite_x509parse.function b/tests/suites/test_suite_x509parse.function
index b522c1a..7e68d1e 100644
--- a/tests/suites/test_suite_x509parse.function
+++ b/tests/suites/test_suite_x509parse.function
@@ -1169,6 +1169,30 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CSR_PARSE_C:!MBEDTLS_X509_REMOVE_INFO */
+void mbedtls_x509_csr_parse_file(char *csr_file, char *ref_out, int ref_ret)
+{
+    mbedtls_x509_csr csr;
+    char my_out[1000];
+    int my_ret;
+
+    mbedtls_x509_csr_init(&csr);
+    memset(my_out, 0, sizeof(my_out));
+
+    my_ret = mbedtls_x509_csr_parse_file(&csr, csr_file);
+    TEST_ASSERT(my_ret == ref_ret);
+
+    if (ref_ret == 0) {
+        size_t my_out_len = mbedtls_x509_csr_info(my_out, sizeof(my_out), "", &csr);
+        TEST_ASSERT(my_out_len == strlen(ref_out));
+        TEST_ASSERT(strcmp(my_out, ref_out) == 0);
+    }
+
+exit:
+    mbedtls_x509_csr_free(&csr);
+}
+/* END_CASE */
+
 /* BEGIN_CASE depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CRT_PARSE_C */
 void mbedtls_x509_crt_parse_path(char *crt_path, int ret, int nb_crt)
 {