Squashed 'lib/mbedtls/external/mbedtls/' content from commit 2ca6c285a0dd

git-subtree-dir: lib/mbedtls/external/mbedtls
git-subtree-split: 2ca6c285a0dd3f33982dd57299012dacab1ff206

1 files changed, 639 insertions, 0 deletions

diff --git a/library/x509_csr.c b/library/x509_csr.c
new file mode 100644
index 00000000000..813d64466cc
--- /dev/null
+++ b/library/x509_csr.c
@@ -0,0 +1,639 @@
+/*
+ *  X.509 Certificate Signing Request (CSR) parsing
+ *
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+/*
+ *  The ITU-T X.509 standard defines a certificate format for PKI.
+ *
+ *  http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
+ *  http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
+ *  http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
+ *
+ *  http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
+ *  http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
+ */
+
+#include "common.h"
+
+#if defined(MBEDTLS_X509_CSR_PARSE_C)
+
+#include "mbedtls/x509_csr.h"
+#include "x509_internal.h"
+#include "mbedtls/error.h"
+#include "mbedtls/oid.h"
+#include "mbedtls/platform_util.h"
+
+#include <string.h>
+
+#if defined(MBEDTLS_PEM_PARSE_C)
+#include "mbedtls/pem.h"
+#endif
+
+#include "mbedtls/platform.h"
+
+#if defined(MBEDTLS_FS_IO) || defined(EFIX64) || defined(EFI32)
+#include <stdio.h>
+#endif
+
+/*
+ *  Version  ::=  INTEGER  {  v1(0)  }
+ */
+static int x509_csr_get_version(unsigned char **p,
+                                const unsigned char *end,
+                                int *ver)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
+    if ((ret = mbedtls_asn1_get_int(p, end, ver)) != 0) {
+        if (ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
+            *ver = 0;
+            return 0;
+        }
+
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_VERSION, ret);
+    }
+
+    return 0;
+}
+
+/*
+ * Parse CSR extension requests in DER format
+ */
+static int x509_csr_parse_extensions(mbedtls_x509_csr *csr,
+                                     unsigned char **p, const unsigned char *end,
+                                     mbedtls_x509_csr_ext_cb_t cb,
+                                     void *p_ctx)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t len;
+    unsigned char *end_ext_data, *end_ext_octet;
+
+    while (*p < end) {
+        mbedtls_x509_buf extn_oid = { 0, 0, NULL };
+        int is_critical = 0; /* DEFAULT FALSE */
+        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;
+
+        /* Get optional critical */
+        if ((ret = mbedtls_asn1_get_bool(p, end_ext_data, &is_critical)) != 0 &&
+            (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG)) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+        }
+
+        /* 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);
+        }
+
+        end_ext_octet = *p + len;
+
+        if (end_ext_octet != 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) {
+            /* Give the callback (if any) a chance to handle the extension */
+            if (cb != NULL) {
+                ret = cb(p_ctx, csr, &extn_oid, is_critical, *p, end_ext_octet);
+                if (ret != 0 && is_critical) {
+                    return ret;
+                }
+                *p = end_ext_octet;
+                continue;
+            }
+
+            /* No parser found, skip extension */
+            *p = end_ext_octet;
+
+            if (is_critical) {
+                /* Data is marked as critical: fail */
+                return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                         MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
+            }
+            continue;
+        }
+
+        /* 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:
+                /*
+                 * If this is a non-critical extension, which the oid layer
+                 * supports, but there isn't an x509 parser for it,
+                 * skip the extension.
+                 */
+                if (is_critical) {
+                    return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
+                } else {
+                    *p = end_ext_octet;
+                }
+        }
+    }
+
+    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,
+                                     mbedtls_x509_csr_ext_cb_t cb,
+                                     void *p_ctx)
+{
+    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, cb, p_ctx)) != 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
+ */
+static int mbedtls_x509_csr_parse_der_internal(mbedtls_x509_csr *csr,
+                                               const unsigned char *buf, size_t buflen,
+                                               mbedtls_x509_csr_ext_cb_t cb,
+                                               void *p_ctx)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t len;
+    unsigned char *p, *end;
+    mbedtls_x509_buf sig_params;
+
+    memset(&sig_params, 0, sizeof(mbedtls_x509_buf));
+
+    /*
+     * Check for valid input
+     */
+    if (csr == NULL || buf == NULL || buflen == 0) {
+        return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
+    }
+
+    mbedtls_x509_csr_init(csr);
+
+    /*
+     * first copy the raw DER data
+     */
+    p = mbedtls_calloc(1, len = buflen);
+
+    if (p == NULL) {
+        return MBEDTLS_ERR_X509_ALLOC_FAILED;
+    }
+
+    memcpy(p, buf, buflen);
+
+    csr->raw.p = p;
+    csr->raw.len = len;
+    end = p + len;
+
+    /*
+     *  CertificationRequest ::= SEQUENCE {
+     *       certificationRequestInfo CertificationRequestInfo,
+     *       signatureAlgorithm AlgorithmIdentifier,
+     *       signature          BIT STRING
+     *  }
+     */
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return MBEDTLS_ERR_X509_INVALID_FORMAT;
+    }
+
+    if (len != (size_t) (end - p)) {
+        mbedtls_x509_csr_free(csr);
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    /*
+     *  CertificationRequestInfo ::= SEQUENCE {
+     */
+    csr->cri.p = p;
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
+    }
+
+    end = p + len;
+    csr->cri.len = (size_t) (end - csr->cri.p);
+
+    /*
+     *  Version  ::=  INTEGER {  v1(0) }
+     */
+    if ((ret = x509_csr_get_version(&p, end, &csr->version)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return ret;
+    }
+
+    if (csr->version != 0) {
+        mbedtls_x509_csr_free(csr);
+        return MBEDTLS_ERR_X509_UNKNOWN_VERSION;
+    }
+
+    csr->version++;
+
+    /*
+     *  subject               Name
+     */
+    csr->subject_raw.p = p;
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
+    }
+
+    if ((ret = mbedtls_x509_get_name(&p, p + len, &csr->subject)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return ret;
+    }
+
+    csr->subject_raw.len = (size_t) (p - csr->subject_raw.p);
+
+    /*
+     *  subjectPKInfo SubjectPublicKeyInfo
+     */
+    if ((ret = mbedtls_pk_parse_subpubkey(&p, end, &csr->pk)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return ret;
+    }
+
+    /*
+     *  attributes    [0] Attributes
+     *
+     *  The list of possible attributes is open-ended, though RFC 2985
+     *  (PKCS#9) defines a few in section 5.4. We currently don't support any,
+     *  so we just ignore them. This is a safe thing to do as the worst thing
+     *  that could happen is that we issue a certificate that does not match
+     *  the requester's expectations - this cannot cause a violation of our
+     *  signature policies.
+     */
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_CONTEXT_SPECIFIC)) !=
+        0) {
+        mbedtls_x509_csr_free(csr);
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
+    }
+
+    if ((ret = x509_csr_parse_attributes(csr, p, p + len, cb, p_ctx)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return ret;
+    }
+
+    p += len;
+
+    end = csr->raw.p + csr->raw.len;
+
+    /*
+     *  signatureAlgorithm   AlgorithmIdentifier,
+     *  signature            BIT STRING
+     */
+    if ((ret = mbedtls_x509_get_alg(&p, end, &csr->sig_oid, &sig_params)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return ret;
+    }
+
+    if ((ret = mbedtls_x509_get_sig_alg(&csr->sig_oid, &sig_params,
+                                        &csr->sig_md, &csr->sig_pk,
+                                        &csr->sig_opts)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG;
+    }
+
+    if ((ret = mbedtls_x509_get_sig(&p, end, &csr->sig)) != 0) {
+        mbedtls_x509_csr_free(csr);
+        return ret;
+    }
+
+    if (p != end) {
+        mbedtls_x509_csr_free(csr);
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    return 0;
+}
+
+/*
+ * Parse a CSR in DER format
+ */
+int mbedtls_x509_csr_parse_der(mbedtls_x509_csr *csr,
+                               const unsigned char *buf, size_t buflen)
+{
+    return mbedtls_x509_csr_parse_der_internal(csr, buf, buflen, NULL, NULL);
+}
+
+/*
+ * Parse a CSR in DER format with callback for unknown extensions
+ */
+int mbedtls_x509_csr_parse_der_with_ext_cb(mbedtls_x509_csr *csr,
+                                           const unsigned char *buf, size_t buflen,
+                                           mbedtls_x509_csr_ext_cb_t cb,
+                                           void *p_ctx)
+{
+    return mbedtls_x509_csr_parse_der_internal(csr, buf, buflen, cb, p_ctx);
+}
+
+/*
+ * Parse a CSR, allowing for PEM or raw DER encoding
+ */
+int mbedtls_x509_csr_parse(mbedtls_x509_csr *csr, const unsigned char *buf, size_t buflen)
+{
+#if defined(MBEDTLS_PEM_PARSE_C)
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t use_len;
+    mbedtls_pem_context pem;
+#endif
+
+    /*
+     * Check for valid input
+     */
+    if (csr == NULL || buf == NULL || buflen == 0) {
+        return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
+    }
+
+#if defined(MBEDTLS_PEM_PARSE_C)
+    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
+    if (buf[buflen - 1] == '\0') {
+        mbedtls_pem_init(&pem);
+        ret = mbedtls_pem_read_buffer(&pem,
+                                      "-----BEGIN CERTIFICATE REQUEST-----",
+                                      "-----END CERTIFICATE REQUEST-----",
+                                      buf, NULL, 0, &use_len);
+        if (ret == MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
+            ret = mbedtls_pem_read_buffer(&pem,
+                                          "-----BEGIN NEW CERTIFICATE REQUEST-----",
+                                          "-----END NEW CERTIFICATE REQUEST-----",
+                                          buf, NULL, 0, &use_len);
+        }
+
+        if (ret == 0) {
+            /*
+             * Was PEM encoded, parse the result
+             */
+            ret = mbedtls_x509_csr_parse_der(csr, pem.buf, pem.buflen);
+        }
+
+        mbedtls_pem_free(&pem);
+        if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
+            return ret;
+        }
+    }
+#endif /* MBEDTLS_PEM_PARSE_C */
+    return mbedtls_x509_csr_parse_der(csr, buf, buflen);
+}
+
+#if defined(MBEDTLS_FS_IO)
+/*
+ * Load a CSR into the structure
+ */
+int mbedtls_x509_csr_parse_file(mbedtls_x509_csr *csr, const char *path)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t n;
+    unsigned char *buf;
+
+    if ((ret = mbedtls_pk_load_file(path, &buf, &n)) != 0) {
+        return ret;
+    }
+
+    ret = mbedtls_x509_csr_parse(csr, buf, n);
+
+    mbedtls_zeroize_and_free(buf, n);
+
+    return ret;
+}
+#endif /* MBEDTLS_FS_IO */
+
+#if !defined(MBEDTLS_X509_REMOVE_INFO)
+#define BEFORE_COLON    14
+#define BC              "14"
+/*
+ * Return an informational string about the CSR.
+ */
+int mbedtls_x509_csr_info(char *buf, size_t size, const char *prefix,
+                          const mbedtls_x509_csr *csr)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t n;
+    char *p;
+    char key_size_str[BEFORE_COLON];
+
+    p = buf;
+    n = size;
+
+    ret = mbedtls_snprintf(p, n, "%sCSR version   : %d",
+                           prefix, csr->version);
+    MBEDTLS_X509_SAFE_SNPRINTF;
+
+    ret = mbedtls_snprintf(p, n, "\n%ssubject name  : ", prefix);
+    MBEDTLS_X509_SAFE_SNPRINTF;
+    ret = mbedtls_x509_dn_gets(p, n, &csr->subject);
+    MBEDTLS_X509_SAFE_SNPRINTF;
+
+    ret = mbedtls_snprintf(p, n, "\n%ssigned using  : ", prefix);
+    MBEDTLS_X509_SAFE_SNPRINTF;
+
+    ret = mbedtls_x509_sig_alg_gets(p, n, &csr->sig_oid, csr->sig_pk, csr->sig_md,
+                                    csr->sig_opts);
+    MBEDTLS_X509_SAFE_SNPRINTF;
+
+    if ((ret = mbedtls_x509_key_size_helper(key_size_str, BEFORE_COLON,
+                                            mbedtls_pk_get_name(&csr->pk))) != 0) {
+        return ret;
+    }
+
+    ret = mbedtls_snprintf(p, n, "\n%s%-" BC "s: %d bits\n", prefix, key_size_str,
+                           (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 */
+
+/*
+ * Initialize a CSR
+ */
+void mbedtls_x509_csr_init(mbedtls_x509_csr *csr)
+{
+    memset(csr, 0, sizeof(mbedtls_x509_csr));
+}
+
+/*
+ * Unallocate all CSR data
+ */
+void mbedtls_x509_csr_free(mbedtls_x509_csr *csr)
+{
+    if (csr == NULL) {
+        return;
+    }
+
+    mbedtls_pk_free(&csr->pk);
+
+#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
+    mbedtls_free(csr->sig_opts);
+#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_zeroize_and_free(csr->raw.p, csr->raw.len);
+    }
+
+    mbedtls_platform_zeroize(csr, sizeof(mbedtls_x509_csr));
+}
+
+#endif /* MBEDTLS_X509_CSR_PARSE_C */