From 8d35a8961052e49922a0eac228f8ddc476845bd5 Mon Sep 17 00:00:00 2001
From: Dan Streetman <ddstreet@ieee.org>
Date: Mon, 6 Nov 2023 13:40:11 -0500
Subject: [PATCH] tpm2: add tpm2_sym_alg_*_string() and
 tpm2_sym_mode_*_string()

Add functions to convert between alg id and string name for symmetric
algorithms and symmetric encryption modes.

(cherry picked from commit 2d784782bf700ae26dbeaa24e11ee8faebc29367)

Related: RHEL-16182
---
 src/shared/tpm2-util.c | 56 ++++++++++++++++++++++++++++++++++++++++++
 src/shared/tpm2-util.h |  6 +++++
 2 files changed, 62 insertions(+)

diff --git a/src/shared/tpm2-util.c b/src/shared/tpm2-util.c
index 4f1aafedf8..2e2a3f5fb0 100644
--- a/src/shared/tpm2-util.c
+++ b/src/shared/tpm2-util.c
@@ -4923,6 +4923,62 @@ int tpm2_asym_alg_from_string(const char *alg) {
         return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Unknown asymmetric algorithm name '%s'", alg);
 }
 
+const char *tpm2_sym_alg_to_string(uint16_t alg) {
+        switch (alg) {
+#if HAVE_TPM2
+        case TPM2_ALG_AES:
+                return "aes";
+#endif
+        default:
+                log_debug("Unknown symmetric algorithm id 0x%" PRIx16, alg);
+                return NULL;
+        }
+}
+
+int tpm2_sym_alg_from_string(const char *alg) {
+#if HAVE_TPM2
+        if (strcaseeq_ptr(alg, "aes"))
+                return TPM2_ALG_AES;
+#endif
+        return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Unknown symmetric algorithm name '%s'", alg);
+}
+
+const char *tpm2_sym_mode_to_string(uint16_t mode) {
+        switch (mode) {
+#if HAVE_TPM2
+        case TPM2_ALG_CTR:
+                return "ctr";
+        case TPM2_ALG_OFB:
+                return "ofb";
+        case TPM2_ALG_CBC:
+                return "cbc";
+        case TPM2_ALG_CFB:
+                return "cfb";
+        case TPM2_ALG_ECB:
+                return "ecb";
+#endif
+        default:
+                log_debug("Unknown symmetric mode id 0x%" PRIx16, mode);
+                return NULL;
+        }
+}
+
+int tpm2_sym_mode_from_string(const char *mode) {
+#if HAVE_TPM2
+        if (strcaseeq_ptr(mode, "ctr"))
+                return TPM2_ALG_CTR;
+        if (strcaseeq_ptr(mode, "ofb"))
+                return TPM2_ALG_OFB;
+        if (strcaseeq_ptr(mode, "cbc"))
+                return TPM2_ALG_CBC;
+        if (strcaseeq_ptr(mode, "cfb"))
+                return TPM2_ALG_CFB;
+        if (strcaseeq_ptr(mode, "ecb"))
+                return TPM2_ALG_ECB;
+#endif
+        return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Unknown symmetric mode name '%s'", mode);
+}
+
 Tpm2Support tpm2_support(void) {
         Tpm2Support support = TPM2_SUPPORT_NONE;
         int r;
diff --git a/src/shared/tpm2-util.h b/src/shared/tpm2-util.h
index bf41bac76e..59c6a6fa92 100644
--- a/src/shared/tpm2-util.h
+++ b/src/shared/tpm2-util.h
@@ -309,6 +309,12 @@ int tpm2_hash_alg_from_string(const char *alg);
 const char *tpm2_asym_alg_to_string(uint16_t alg);
 int tpm2_asym_alg_from_string(const char *alg);
 
+const char *tpm2_sym_alg_to_string(uint16_t alg) _const_;
+int tpm2_sym_alg_from_string(const char *alg) _pure_;
+
+const char *tpm2_sym_mode_to_string(uint16_t mode) _const_;
+int tpm2_sym_mode_from_string(const char *mode) _pure_;
+
 char *tpm2_pcr_mask_to_string(uint32_t mask);
 
 typedef struct {