diff --git a/Makefile b/Makefile
index 3d8943e..c108f87 100644
--- a/Makefile
+++ b/Makefile
@@ -46,7 +46,7 @@
     fw/mtrr.c fw/xen.c fw/acpi.c fw/mptable.c fw/pirtable.c		\
     fw/smbios.c fw/romfile_loader.c fw/dsdt_parser.c hw/virtio-ring.c	\
     hw/virtio-pci.c hw/virtio-mmio.c hw/virtio-blk.c hw/virtio-scsi.c	\
-    hw/tpm_drivers.c hw/nvme.c
+    hw/tpm_drivers.c hw/nvme.c sha256.c sha512.c
 SRC32SEG=string.c output.c pcibios.c apm.c stacks.c hw/pci.c hw/serialio.c
 DIRS=src src/hw src/fw vgasrc
 
diff --git a/src/sha.h b/src/sha.h
new file mode 100644
index 0000000..edc9437
--- /dev/null
+++ b/src/sha.h
@@ -0,0 +1,11 @@
+#ifndef __SHA_H
+#define __SHA_H
+
+#include "types.h" // u32
+
+void sha1(const u8 *data, u32 length, u8 *hash);
+void sha256(const u8 *data, u32 length, u8 *hash);
+void sha384(const u8 *data, u32 length, u8 *hash);
+void sha512(const u8 *data, u32 length, u8 *hash);
+
+#endif // sha.h
diff --git a/src/sha1.c b/src/sha1.c
index 2ecb3cb..e6d80c8 100644
--- a/src/sha1.c
+++ b/src/sha1.c
@@ -13,7 +13,7 @@
 
 #include "config.h"
 #include "byteorder.h" // cpu_to_*, __swab64
-#include "sha1.h" // sha1
+#include "sha.h" // sha1
 #include "string.h" // memcpy
 #include "x86.h" // rol
 
@@ -126,11 +126,11 @@
 }
 
 
-u32
+void
 sha1(const u8 *data, u32 length, u8 *hash)
 {
     if (!CONFIG_TCGBIOS)
-        return 0;
+        return;
 
     sha1_ctx ctx = {
         .h[0] = 0x67452301,
@@ -143,5 +143,5 @@
     sha1_do(&ctx, data, length);
     memcpy(hash, &ctx.h[0], 20);
 
-    return 0;
+    return;
 }
diff --git a/src/sha1.h b/src/sha1.h
deleted file mode 100644
index 07aabf3..0000000
--- a/src/sha1.h
+++ /dev/null
@@ -1,8 +0,0 @@
-#ifndef __SHA1_H
-#define __SHA1_H
-
-#include "types.h" // u32
-
-u32 sha1(const u8 *data, u32 length, u8 *hash);
-
-#endif // sha1.h
diff --git a/src/sha256.c b/src/sha256.c
new file mode 100644
index 0000000..72c3df8
--- /dev/null
+++ b/src/sha256.c
@@ -0,0 +1,211 @@
+/*****************************************************************************
+ * Copyright (c) 2015-2020 IBM Corporation
+ * All rights reserved.
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     IBM Corporation - initial implementation
+ *****************************************************************************/
+
+/*
+ *  See: NIST standard for SHA-256 in FIPS PUB 180-4
+ */
+
+#include "config.h"
+#include "byteorder.h"
+#include "sha.h"
+#include "string.h"
+#include "x86.h"
+
+typedef struct _sha256_ctx {
+    u32 h[8];
+} sha256_ctx;
+
+static inline u32 Ch(u32 x, u32 y, u32 z)
+{
+    return (x & y) | ((x ^ 0xffffffff) & z);
+}
+
+static inline u32 Maj(u32 x, u32 y, u32 z)
+{
+    return (x & y) | (x & z) | (y & z);
+}
+
+static inline u32 sum0(u32 x)
+{
+    return ror(x, 2) ^ ror(x, 13) ^ ror(x, 22);
+}
+
+static inline u32 sum1(u32 x)
+{
+    return ror(x, 6) ^ ror(x, 11) ^ ror(x, 25);
+}
+
+static inline u32 sigma0(u32 x)
+{
+    return ror(x, 7) ^ ror(x, 18) ^ (x >> 3);
+}
+
+static inline u32 sigma1(u32 x)
+{
+    return ror(x, 17) ^ ror(x, 19) ^ (x >> 10);
+}
+
+static void sha256_block(u32 *w, sha256_ctx *ctx)
+{
+    u32 t;
+    u32 a, b, c, d, e, f, g, h;
+    u32 T1, T2;
+
+    /*
+     * FIPS 180-4 4.2.2: SHA256 Constants
+     */
+    static const u32 sha_ko[64] = {
+        0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
+        0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
+        0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
+        0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
+        0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
+        0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
+        0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
+        0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
+        0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
+        0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+        0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
+        0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
+        0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
+        0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
+        0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
+        0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
+    };
+
+    /*
+     * FIPS 180-4 6.2.2: step 1
+     *
+     *  0 <= i <= 15:
+     *    W(t) = M(t)
+     * 16 <= i <= 63:
+     *    W(t) = sigma1(W(t-2)) + W(t-7) + sigma0(W(t-15)) + W(t-16)
+     */
+
+    /* w(0)..w(15) are in big endian format */
+    for (t = 0; t <= 15; t++)
+        w[t] = be32_to_cpu(w[t]);
+
+    for (t = 16; t <= 63; t++)
+        w[t] = sigma1(w[t-2]) + w[t-7] + sigma0(w[t-15]) + w[t-16];
+
+    /*
+     * step 2: a = H0, b = H1, c = H2, d = H3, e = H4, f = H5, g = H6, h = H7
+     */
+    a = ctx->h[0];
+    b = ctx->h[1];
+    c = ctx->h[2];
+    d = ctx->h[3];
+    e = ctx->h[4];
+    f = ctx->h[5];
+    g = ctx->h[6];
+    h = ctx->h[7];
+
+    /*
+     * step 3: For i = 0 to 63:
+     *    T1 = h + sum1(e) + Ch(e,f,g) + K(t) + W(t);
+     *    T2 = sum0(a) + Maj(a,b,c)
+     *    h = g; g = f; f = e; e = d + T1; d = c; c = b; b = a; a + T1 + T2
+     */
+    for (t = 0; t <= 63; t++) {
+        T1 = h + sum1(e) + Ch(e, f, g) + sha_ko[t] + w[t];
+        T2 = sum0(a) + Maj(a, b, c);
+        h = g;
+        g = f;
+        f = e;
+        e = d + T1;
+        d = c;
+        c = b;
+        b = a;
+        a = T1 + T2;
+    }
+
+    /*
+     * step 4:
+     *    H0 = a + H0, H1 = b + H1, H2 = c + H2, H3 = d + H3, H4 = e + H4
+     */
+    ctx->h[0] += a;
+    ctx->h[1] += b;
+    ctx->h[2] += c;
+    ctx->h[3] += d;
+    ctx->h[4] += e;
+    ctx->h[5] += f;
+    ctx->h[6] += g;
+    ctx->h[7] += h;
+}
+
+static void sha256_do(sha256_ctx *ctx, const u8 *data32, u32 length)
+{
+    u32 offset;
+    u16 num;
+    u32 bits = 0;
+    u32 w[64];
+    u64 tmp;
+
+    /* treat data in 64-byte chunks */
+    for (offset = 0; length - offset >= 64; offset += 64) {
+        memcpy(w, data32 + offset, 64);
+        sha256_block((u32 *)w, ctx);
+        bits += (64 * 8);
+    }
+
+    /* last block with less than 64 bytes */
+    num = length - offset;
+    bits += (num << 3);
+
+    memcpy(w, data32 + offset, num);
+    /*
+     * FIPS 180-4 5.1: Padding the Message
+     */
+    ((u8 *)w)[num] = 0x80;
+    if (64 - (num + 1) > 0)
+        memset( &((u8 *)w)[num + 1], 0, 64 - (num + 1));
+
+    if (num >= 56) {
+        /* cannot append number of bits here */
+        sha256_block((u32 *)w, ctx);
+        memset(w, 0, 60);
+    }
+
+    /* write number of bits to end of block */
+    tmp = cpu_to_be64(bits);
+    memcpy(&w[14], &tmp, 8);
+
+    sha256_block(w, ctx);
+
+    /* need to switch result's endianness */
+    for (num = 0; num < 8; num++)
+        ctx->h[num] = cpu_to_be32(ctx->h[num]);
+}
+
+void sha256(const u8 *data, u32 length, u8 *hash)
+{
+    sha256_ctx ctx = {
+        .h = {
+            /*
+             * FIPS 180-4: 6.2.1
+             *   -> 5.3.3: initial hash value
+             */
+            0x6a09e667,
+            0xbb67ae85,
+            0x3c6ef372,
+            0xa54ff53a,
+            0x510e527f,
+            0x9b05688c,
+            0x1f83d9ab,
+            0x5be0cd19
+        }
+    };
+
+    sha256_do(&ctx, data, length);
+    memcpy(hash, ctx.h, sizeof(ctx.h));
+}
diff --git a/src/sha512.c b/src/sha512.c
new file mode 100644
index 0000000..fddd9fa
--- /dev/null
+++ b/src/sha512.c
@@ -0,0 +1,244 @@
+/*****************************************************************************
+ * Copyright (c) 2021 IBM Corporation
+ * All rights reserved.
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     IBM Corporation - initial implementation
+ *****************************************************************************/
+
+/*
+ *  See: NIST standard for SHA-512 and SHA-384 in FIPS PUB 180-4 & RFC 6234
+ */
+
+#include "config.h"
+#include "byteorder.h"
+#include "sha.h"
+#include "string.h"
+
+typedef struct _sha512_ctx {
+    u64 h[8];
+} sha512_ctx;
+
+static inline u64 ror64(u64 x, u8 n)
+{
+    return (x >> n) | (x << (64 - n));
+}
+
+static inline u64 Ch64(u64 x, u64 y, u64 z)
+{
+    return (x & y) ^ ((x ^ 0xffffffffffffffffULL) & z);
+}
+
+static inline u64 Maj64(u64 x, u64 y, u64 z)
+{
+    return (x & y) ^ (x & z) ^ (y & z);
+}
+
+static inline u64 sum0_64(u64 x)
+{
+    return ror64(x, 28) ^ ror64(x, 34) ^ ror64(x, 39);
+}
+
+static inline u64 sum1_64(u64 x)
+{
+    return ror64(x, 14) ^ ror64(x, 18) ^ ror64(x, 41);
+}
+
+static inline u64 sigma0_64(u64 x)
+{
+    return ror64(x, 1) ^ ror64(x, 8) ^ (x >> 7);
+}
+
+static inline u64 sigma1_64(u64 x)
+{
+    return ror64(x, 19) ^ ror64(x, 61) ^ (x >> 6);
+}
+
+static void sha512_block(u64 *w, sha512_ctx *ctx)
+{
+    u32 t;
+    u64 a, b, c, d, e, f, g, h;
+    u64 T1, T2;
+
+    /*
+     * FIPS 180-4 4.2.2: SHA512 Constants
+     */
+    static const u64 sha_ko[80] = {
+        0x428a2f98d728ae22, 0x7137449123ef65cd, 0xb5c0fbcfec4d3b2f, 0xe9b5dba58189dbbc,
+        0x3956c25bf348b538, 0x59f111f1b605d019, 0x923f82a4af194f9b, 0xab1c5ed5da6d8118,
+        0xd807aa98a3030242, 0x12835b0145706fbe, 0x243185be4ee4b28c, 0x550c7dc3d5ffb4e2,
+        0x72be5d74f27b896f, 0x80deb1fe3b1696b1, 0x9bdc06a725c71235, 0xc19bf174cf692694,
+        0xe49b69c19ef14ad2, 0xefbe4786384f25e3, 0x0fc19dc68b8cd5b5, 0x240ca1cc77ac9c65,
+        0x2de92c6f592b0275, 0x4a7484aa6ea6e483, 0x5cb0a9dcbd41fbd4, 0x76f988da831153b5,
+        0x983e5152ee66dfab, 0xa831c66d2db43210, 0xb00327c898fb213f, 0xbf597fc7beef0ee4,
+        0xc6e00bf33da88fc2, 0xd5a79147930aa725, 0x06ca6351e003826f, 0x142929670a0e6e70,
+        0x27b70a8546d22ffc, 0x2e1b21385c26c926, 0x4d2c6dfc5ac42aed, 0x53380d139d95b3df,
+        0x650a73548baf63de, 0x766a0abb3c77b2a8, 0x81c2c92e47edaee6, 0x92722c851482353b,
+        0xa2bfe8a14cf10364, 0xa81a664bbc423001, 0xc24b8b70d0f89791, 0xc76c51a30654be30,
+        0xd192e819d6ef5218, 0xd69906245565a910, 0xf40e35855771202a, 0x106aa07032bbd1b8,
+        0x19a4c116b8d2d0c8, 0x1e376c085141ab53, 0x2748774cdf8eeb99, 0x34b0bcb5e19b48a8,
+        0x391c0cb3c5c95a63, 0x4ed8aa4ae3418acb, 0x5b9cca4f7763e373, 0x682e6ff3d6b2b8a3,
+        0x748f82ee5defb2fc, 0x78a5636f43172f60, 0x84c87814a1f0ab72, 0x8cc702081a6439ec,
+        0x90befffa23631e28, 0xa4506cebde82bde9, 0xbef9a3f7b2c67915, 0xc67178f2e372532b,
+        0xca273eceea26619c, 0xd186b8c721c0c207, 0xeada7dd6cde0eb1e, 0xf57d4f7fee6ed178,
+        0x06f067aa72176fba, 0x0a637dc5a2c898a6, 0x113f9804bef90dae, 0x1b710b35131c471b,
+        0x28db77f523047d84, 0x32caab7b40c72493, 0x3c9ebe0a15c9bebc, 0x431d67c49c100d4c,
+        0x4cc5d4becb3e42b6, 0x597f299cfc657e2a, 0x5fcb6fab3ad6faec, 0x6c44198c4a475817
+    };
+
+    /*
+     * FIPS 180-4 6.4.2: step 1
+     *
+     *  0 <= i <= 15:
+     *    W(t) = M(t)
+     * 16 <= i <= 79:
+     *    W(t) = sigma1(W(t-2)) + W(t-7) + sigma0(W(t-15)) + W(t-16)
+     */
+
+    /* w(0)..w(15) are in big endian format */
+    for (t = 0; t <= 15; t++)
+        w[t] = be64_to_cpu(w[t]);
+
+    for (t = 16; t <= 79; t++)
+        w[t] = sigma1_64(w[t-2]) + w[t-7] + sigma0_64(w[t-15]) + w[t-16];
+
+    /*
+     * step 2: a = H0, b = H1, c = H2, d = H3, e = H4, f = H5, g = H6, h = H7
+     */
+    a = ctx->h[0];
+    b = ctx->h[1];
+    c = ctx->h[2];
+    d = ctx->h[3];
+    e = ctx->h[4];
+    f = ctx->h[5];
+    g = ctx->h[6];
+    h = ctx->h[7];
+
+    /*
+     * step 3: For i = 0 to 79:
+     *    T1 = h + sum1(e) + Ch(e,f,g) + K(t) + W(t);
+     *    T2 = sum0(a) + Maj(a,b,c)
+     *    h = g; g = f; f = e; e = d + T1; d = c; c = b; b = a; a + T1 + T2
+     */
+    for (t = 0; t <= 79; t++) {
+        T1 = h + sum1_64(e) + Ch64(e, f, g) + sha_ko[t] + w[t];
+        T2 = sum0_64(a) + Maj64(a, b, c);
+        h = g;
+        g = f;
+        f = e;
+        e = d + T1;
+        d = c;
+        c = b;
+        b = a;
+        a = T1 + T2;
+    }
+
+    /*
+     * step 4:
+     *    H0 = a + H0, H1 = b + H1, H2 = c + H2, H3 = d + H3, H4 = e + H4
+     */
+    ctx->h[0] += a;
+    ctx->h[1] += b;
+    ctx->h[2] += c;
+    ctx->h[3] += d;
+    ctx->h[4] += e;
+    ctx->h[5] += f;
+    ctx->h[6] += g;
+    ctx->h[7] += h;
+}
+
+static void sha512_do(sha512_ctx *ctx, const u8 *data32, u32 length)
+{
+    u32 offset;
+    u16 num;
+    u64 bits = 0;
+    u64 w[80];
+    u64 tmp;
+
+    /* treat data in 128-byte/1024 bit chunks */
+    for (offset = 0; length - offset >= 128; offset += 128) {
+        memcpy(w, data32 + offset, 128);
+        sha512_block(w, ctx);
+        bits += (128 * 8);
+    }
+
+    /* last block with less than 128 bytes */
+    num = length - offset;
+    bits += (num << 3);
+
+    memcpy(w, data32 + offset, num);
+    /*
+     * FIPS 180-4 5.1: Padding the Message
+     */
+    ((u8 *)w)[num] = 0x80;
+    if (128 - (num + 1) > 0)
+        memset( &((u8 *)w)[num + 1], 0, 128 - (num + 1));
+
+    if (num >= 112) {
+        /* cannot append number of bits here;
+         * need space for 128 bits (16 bytes)
+         */
+        sha512_block((u64 *)w, ctx);
+        memset(w, 0, 128);
+    }
+
+    /* write number of bits to end of the block; we write 64 bits */
+    tmp = cpu_to_be64(bits);
+    memcpy(&w[15], &tmp, 8);
+
+    sha512_block(w, ctx);
+
+    /* need to switch result's endianness */
+    for (num = 0; num < 8; num++)
+        ctx->h[num] = cpu_to_be64(ctx->h[num]);
+}
+
+void sha384(const u8 *data, u32 length, u8 *hash)
+{
+    sha512_ctx ctx = {
+        .h = {
+            /*
+             * FIPS 180-4: 6.2.1
+             *   -> 5.3.4: initial hash value
+             */
+            0xcbbb9d5dc1059ed8,
+            0x629a292a367cd507,
+            0x9159015a3070dd17,
+            0x152fecd8f70e5939,
+            0x67332667ffc00b31,
+            0x8eb44a8768581511,
+            0xdb0c2e0d64f98fa7,
+            0x47b5481dbefa4fa4
+        }
+    };
+
+    sha512_do(&ctx, data, length);
+    memcpy(hash, ctx.h, 384/8);
+}
+
+void sha512(const u8 *data, u32 length, u8 *hash)
+{
+    sha512_ctx ctx = {
+        .h = {
+            /*
+             * FIPS 180-4: 6.2.1
+             *   -> 5.3.5: initial hash value
+             */
+            0x6a09e667f3bcc908,
+            0xbb67ae8584caa73b,
+            0x3c6ef372fe94f82b,
+            0xa54ff53a5f1d36f1,
+            0x510e527fade682d1,
+            0x9b05688c2b3e6c1f,
+            0x1f83d9abfb41bd6b,
+            0x5be0cd19137e2179
+        }
+    };
+
+    sha512_do(&ctx, data, length);
+    memcpy(hash, ctx.h, sizeof(ctx.h));
+}
diff --git a/src/tcgbios.c b/src/tcgbios.c
index 4150aa0..a9d62c8 100644
--- a/src/tcgbios.c
+++ b/src/tcgbios.c
@@ -16,7 +16,7 @@
 #include "fw/paravirt.h" // runningOnXen
 #include "hw/tpm_drivers.h" // tpm_drivers[]
 #include "output.h" // dprintf
-#include "sha1.h" // sha1
+#include "sha.h" // sha1, sha256, ...
 #include "std/acpi.h"  // RSDP_SIGNATURE, rsdt_descriptor
 #include "std/smbios.h" // struct smbios_entry_point
 #include "std/tcg.h" // TCG_PC_LOGOVERFLOW
diff --git a/src/x86.h b/src/x86.h
index c7bb60d..43a9e6d 100644
--- a/src/x86.h
+++ b/src/x86.h
@@ -140,6 +140,13 @@
     return res;
 }
 
+static inline u32 ror(u32 val, u16 ror) {
+    u32 res;
+    asm volatile("rorl %%cl, %%eax"
+                 : "=a" (res) : "a" (val), "c" (ror));
+    return res;
+}
+
 static inline void outb(u8 value, u16 port) {
     __asm__ __volatile__("outb %b0, %w1" : : "a"(value), "Nd"(port));
 }