1 /* 2 * Copyright 2025 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #include <string.h> 11 #include <openssl/crypto.h> 12 #include <openssl/err.h> 13 #include <openssl/proverr.h> 14 #include "ml_common_codecs.h" 15 16 static int pref_cmp(const void *va, const void *vb) 17 { 18 const ML_COMMON_PKCS8_FMT_PREF *a = va; 19 const ML_COMMON_PKCS8_FMT_PREF *b = vb; 20 21 /* 22 * Zeros sort last, otherwise the sort is in increasing order. 23 * 24 * The preferences are small enough to ensure the comparison is transitive 25 * as required by qsort(3). When overflow or underflow is possible, the 26 * correct transitive comparison would be: (b < a) - (a < b). 27 */ 28 if (a->pref > 0 && b->pref > 0) 29 return a->pref - b->pref; 30 /* A preference of 0 is "larger" than (sorts after) any nonzero value. */ 31 return b->pref - a->pref; 32 } 33 34 ML_COMMON_PKCS8_FMT_PREF * 35 ossl_ml_common_pkcs8_fmt_order(const char *algorithm_name, 36 const ML_COMMON_PKCS8_FMT *p8fmt, 37 const char *direction, const char *formats) 38 { 39 ML_COMMON_PKCS8_FMT_PREF *ret; 40 int i, count = 0; 41 const char *fmt = formats, *end; 42 const char *sep = "\t ,"; 43 44 /* Reserve an extra terminal slot with fmt == NULL */ 45 if ((ret = OPENSSL_zalloc((NUM_PKCS8_FORMATS + 1) * sizeof(*ret))) == NULL) 46 return NULL; 47 48 /* Entries that match a format will get a non-zero preference. */ 49 for (i = 0; i < NUM_PKCS8_FORMATS; ++i) { 50 ret[i].fmt = &p8fmt[i]; 51 ret[i].pref = 0; 52 } 53 54 /* Default to compile-time table order when none specified. */ 55 if (formats == NULL) 56 return ret; 57 58 /* 59 * Formats are case-insensitive, separated by spaces, tabs or commas. 60 * Duplicate formats are allowed, the first occurence determines the order. 61 */ 62 do { 63 if (*(fmt += strspn(fmt, sep)) == '\0') 64 break; 65 end = fmt + strcspn(fmt, sep); 66 for (i = 0; i < NUM_PKCS8_FORMATS; ++i) { 67 /* Skip slots already selected or with a different name. */ 68 if (ret[i].pref > 0 69 || OPENSSL_strncasecmp(ret[i].fmt->p8_name, 70 fmt, (end - fmt)) != 0) 71 continue; 72 /* First time match */ 73 ret[i].pref = ++count; 74 break; 75 } 76 fmt = end; 77 } while (count < NUM_PKCS8_FORMATS); 78 79 /* No formats matched, raise an error */ 80 if (count == 0) { 81 OPENSSL_free(ret); 82 ERR_raise_data(ERR_LIB_PROV, PROV_R_ML_DSA_NO_FORMAT, 83 "no %s private key %s formats are enabled", 84 algorithm_name, direction); 85 return NULL; 86 } 87 /* Sort by preference, with 0's last */ 88 qsort(ret, NUM_PKCS8_FORMATS, sizeof(*ret), pref_cmp); 89 /* Terminate the list at first unselected entry, perhaps reserved slot. */ 90 ret[count].fmt = NULL; 91 return ret; 92 } 93